PCI e description. Why you need a pci-e pci adapter - a detailed guide

WiFi modules and other similar devices. The development of this bus was started by Intel in 2002. Now the non-profit organization PCI Special Interest Group is developing new versions of this bus.

On the this moment The PCI Express bus has completely replaced such obsolete buses as AGP, PCI and PCI-X. The PCI Express bus is located at the bottom of the motherboard in a horizontal position.

PCI Express is a bus that was developed from the PCI bus. The main differences between PCI Express and PCI lie at the physical level. While PCI uses a common bus, PCI Express uses a star topology. Each device is connected to a common switch with a separate connection.

The software model of PCI Express largely repeats the PCI model. Therefore, most existing PCI controllers can be easily modified to use the PCI Express bus.

PCI Express and PCI slots on motherboard

In addition, the PCI Express bus supports new features such as:

• Hot plug devices;
• Guaranteed data exchange rate;
• Energy management;
• Control of the integrity of transmitted information;

How the PCI Express Bus Works

The PCI Express bus uses a bidirectional serial connection to connect devices. Moreover, such a connection can have one (x1) or several (x2, x4, x8, x12, x16 and x32) separate lines. The more such lines are used, the more data transfer speed the PCI Express bus can provide. Depending on the number of lines supported, the sort size on the motherboard will differ. There are slots with one (x1), four (x4) and sixteen (x16) lines.

Visual demonstration of the dimensions of the PCI Express slot

At the same time, any PCI Express device can work in any slot if the slot has the same or more lanes. This allows you to install a PCI Express card with a x1 slot in a x16 slot on the motherboard.

The throughput of PCI Express depends on the number of lanes and the bus version.

One way / two ways in Gbps
	Number of lines
PCIe 1.0	2/4	4/8	8/16	16/32	24/48	32/64	64/128
PCIe 2.0	4/8	8/16	16/32	32/64	48/96	64/128	128/256
PCIe 3.0	8/16	16/32	32/64	64/128	96/192	128/256	256/512
PCIe 4.0	16/32	32/64	64/128	128/256	192/384	256/512	512/1024

Examples of PCI Express Devices

First of all, PCI Express is used to connect discrete graphics cards. Since the advent of this bus, absolutely all video cards use it.

GIGABYTE graphics card GeForce GTX 770

However, this is not all that the PCI Express bus can do. It is used by manufacturers of other components.

SUS Xonar DX sound card

OCZ Z-Drive R4 Enterprise SSD

Support for the PCI Express 3.0 interface in motherboards - a real advantage or a marketing ploy?

During the last months in model range different manufacturers motherboards began to appear, which declared support for the PCI Express 3.0 interface. ASRock, MSI and GIGABYTE were the first to announce such solutions. However, at the moment, there are absolutely no chipsets, graphics and central processors on the market that would support the PCI Express 3.0 interface.

Recall that the PCI Express 3.0 standard was approved last year. It has numerous advantages over its predecessors, so it is not surprising that graphics card and motherboard manufacturers want to implement it in their solutions as soon as possible. However, the currently existing chipsets from Intel and AMD are limited to supporting the PCI Express 2.0 standard. The only hope to take advantage of the PCI Express 3.0 interface in the near future lies with new Intel processors Ivy Bridge, the announcement of which is scheduled only for March-April next year. These processors have an integrated PCI Express 3.0 bus controller, but only graphics chips will be able to use it, since other components use the chipset controller.

Note that the matter is not limited to just replacing the processor. Additional update needed BIOS settings and chipset firmware. In addition, on motherboards with several PCI Express x16 slots, there is a problem with "switches" - small microcircuits that are located near each slot and are responsible for the operational reconfiguration of the number of dedicated lines. These "switches" must also be compatible with the PCI Express 3.0 interface. It should be noted that nForce 200 or Lucid bridge chips support only the PCI Express 2.0 standard and they cannot work with the PCI Express 3.0 specification.

The last argument is that at the moment motherboard manufacturers do not have engineering samples of new Intel Ivy Bridge processors or new graphics chips that support the PCI Express 3.0 specification at the hardware level. Therefore, the announced compatibility with this high-speed interface is theoretical and cannot, at the moment, be practically confirmed.

Thus, support for the PCI Express 3.0 specification by modern motherboards is purely a marketing ploy, the benefits from which the user will be able to get only in a few months by replacing the processor and updating the software components.

When changing only one video card, be sure to take into account that new models may simply not fit your motherboard, since there are not just several different types expansion slots, but also several different versions of them (applicable to both AGP and PCI Express). If you are unsure of your knowledge on this topic, read the section carefully.

As we noted above, the video card is inserted into a special expansion slot on the computer's motherboard, through this slot the video chip exchanges information with the system's central processor. Motherboards most often have one or two different types of expansion slots, differing in bandwidth, power settings and other characteristics, and not all of them are suitable for installing video cards. It is important to know the connectors available in the system and buy only the video card that matches them. Different expansion slots are physically and logically incompatible, and a video card designed for one type will not fit into another and will not work.

Fortunately, not only ISA and VESA Local Bus expansion slots (which are of interest only to future archaeologists) and their corresponding video cards have faded into oblivion, but video cards for PCI slots have practically disappeared, and all AGP models are hopelessly outdated. And all modern GPUs use only one type of interface - PCI Express. Previously, the AGP standard was widely used, these interfaces differ significantly from each other, including the bandwidth provided by the possibilities for powering the video card, as well as other less important characteristics.

Only a very small part of modern motherboards do not have PCI Express slots, and if your system is so old that it uses an AGP video card, then you will not be able to upgrade it - you need to change the entire system. Consider these interfaces in more detail, these are the slots you need to look for on your motherboards. See photos and compare.

AGP (Accelerated Graphics Port or Advanced Graphics Port) is a high-speed interface based on the PCI specification, but designed specifically for connecting graphics cards and motherboards. The AGP bus, although better suited for video adapters than PCI (not Express!), provides a direct connection between the CPU and the video chip, as well as some other features that increase performance in some cases, for example, GART - the ability to read textures directly from random access memory, without copying them to video memory; a higher clock frequency, simplified data transfer protocols, etc., but this type of slots is hopelessly outdated and new products with it have not been released for a long time.

But still, for the sake of order, we will also mention this type. The AGP specifications appeared in 1997, when Intel released the first version of the description, including two speeds: 1x and 2x. In the second version (2.0), AGP 4x appeared, and in 3.0 - 8x. Let's consider all the options in more detail:
AGP 1x is a 32-bit channel running at 66 MHz with a throughput of 266 MB/s, which is twice the bandwidth of PCI (133 MB/s, 33 MHz and 32 bits).
AGP 2x is a 32-bit channel that operates at twice the bandwidth of 533 MB/s at the same frequency of 66 MHz by transmitting data on two fronts, similarly DDR memory(only for the direction "to the video card").
AGP 4x is the same 32-bit channel operating at 66 MHz, but as a result of further tricks, a quadruple "effective" frequency of 266 MHz was achieved, with a maximum throughput of more than 1 GB / s.
AGP 8x - additional changes in this modification made it possible to obtain a throughput of up to 2.1 GB / s.

Video cards with AGP interface and corresponding slots on motherboards are compatible within certain limits. Graphics cards rated for 1.5V do not work in 3.3V slots, and vice versa. However, there are universal connectors that support both types of boards. Video cards designed for the morally and physically obsolete AGP slot have not been considered for a long time, so to learn about old AGP systems, it would be better to read the article:

PCI Express (PCIe or PCI-E, not to be confused with PCI-X), formerly known as Arapahoe or 3GIO, differs from PCI and AGP in that it is a serial rather than a parallel interface, allowing for fewer pins and higher bandwidth. PCIe is just one example of the transition from parallel to serial buses, other examples of this movement are HyperTransport, Serial ATA, USB and FireWire. An important advantage of PCI Express is that it allows you to stack several single lanes into one channel to increase throughput. The versatility of the serial design increases flexibility, slower devices can be assigned fewer lines with fewer pins, and fast devices more.

The PCIe 1.0 interface passes data at 250 MB/s per lane, nearly double the capacity regular slots PCI. The maximum number of lanes supported by PCI Express 1.0 slots is 32, which gives a throughput of up to 8 GB/s. And the PCIe slot with eight working lines is roughly comparable in this parameter to the fastest version of AGP - 8x. What is even more impressive when you consider the possibility of simultaneous transmission in both directions at high speed. The most common PCI Express x1 slots provide a single lane (250 MB/s) throughput in each direction, while PCI Express x16, which is used for video cards and which combines 16 lanes, provides up to 4 GB/s throughput in each direction.

Although the connection between two PCIe devices is sometimes made up of several lines, all devices support a single line at a minimum, but can optionally work with a large number of them. Physically, PCIe expansion cards come in and work fine in any slots with equal or large quantity lines, so a PCI Express x1 card will work quietly in x4 and x16 slots. Also, a physically larger slot can work with a logically smaller number of lines (for example, it looks like a regular x16 connector, but only 8 lines are routed). In any of the above options, PCIe will choose the highest possible mode by itself, and it will work fine.

Most often, x16 connectors are used for video adapters, but there are also boards with x1 connectors. And most motherboards with two PCI Express x16 slots operate in x8 mode to create SLI and CrossFire systems. Physically, other slot options, such as x4, are not used for video cards. Please note that this only applies to physical layer, there are also motherboards with physical PCI-E x16 slots, but in reality with divorced 8, 4 or even 1 channels. And any video cards designed for 16 channels will work in such slots, but with lower performance. By the way, the photo above shows x16, x4 and x1 slots, and PCI is also left for comparison (bottom).

Although the difference in games is not so big. Here, for example, is a review of two motherboards on our website, which examines the difference in the speed of 3D games on two motherboards, a pair of test video cards in which operate in 8-channel and 1-channel modes, respectively:

The comparison that interests us is at the end of the article, pay attention to the last two tables. As you can see, the difference at medium settings is very small, but in heavy modes it begins to increase, moreover, a large difference was noted in the case of a less powerful video card. Take note.

PCI Express differs not only in bandwidth, but also in new power consumption capabilities. This need arose because the AGP 8x slot (version 3.0) can transmit only no more than 40-odd watts in total, which was already lacking for video cards of the then generations designed for AGP, which were equipped with one or two standard four-pin power connectors. Up to 75 watts can be transferred through the PCI Express connector, and an additional 75 watts is received through the standard six-pin power connector (see the last section of this part). Recently, video cards with two such connectors have appeared, which in total gives up to 225 watts.

Subsequently, the PCI-SIG group, which develops the relevant standards, introduced the main specifications for PCI Express 2.0. The second version of PCIe doubled the standard bandwidth from 2.5 Gb/s to 5 Gb/s, so that the x16 slot can transfer data at speeds up to 8 Gb/s in each direction. While PCIe 2.0 is compatible with PCIe 1.1, older expansion cards usually work fine in new motherboards.

The PCIe 2.0 specification supports both 2.5 Gb/s and 5 Gb/s transfer rates, this is done for backwards compatibility with existing solutions PCIe 1.0 and 1.1. PCI Express 2.0 backwards compatibility allows legacy 2.5 Gb/s solutions to be used in 5.0 Gb/s slots, which will simply run at a slower speed. And devices designed to version 2.0 specifications can support 2.5Gbps and/or 5Gbps speeds.

Although the main innovation in PCI Express 2.0 is the speed doubled to 5 Gb/s, but this is not the only change, there are other modifications to increase flexibility, new mechanisms for program control connection speed, etc. We are most interested in changes related to the power supply of devices, as the power requirements of video cards are steadily increasing. PCI-SIG has developed a new specification to accommodate the increasing power consumption of graphics cards, it expands the current power supply capabilities to 225/300W per graphics card. To support this specification, a new 2x4-pin power connector is used, designed to provide power to high-end graphics cards.

Video cards and motherboards with PCI Express 2.0 support appeared on the market already in 2007, and now there are no others on the market. Both major GPU manufacturers, AMD and NVIDIA, have released new GPU and video card lines based on them, supporting the increased bandwidth of the second version of PCI Express and taking advantage of new power supply options for expansion cards. All of them are backwards compatible with motherboards that have PCI Express 1.x slots onboard, although in some rare cases there is incompatibility, so you need to be careful.

Actually, the appearance of the third version of PCIe was an obvious event. In November 2010, the specifications of the third version of PCI Express were finally approved. Although this interface has a transfer rate of 8 gigatransactions / s instead of 5 Gt / s in version 2.0, its throughput has again increased exactly twice compared to the PCI Express 2.0 standard. For this, a different coding scheme was used for data sent over the bus, but compatibility with previous versions PCI Express was preserved at the same time. The first products of the PCI Express 3.0 version were introduced in the summer of 2011, and real devices have just begun to appear on the market.

A whole war broke out among motherboard manufacturers for the right to be the first to introduce a product with PCI Express 3.0 support (mainly based on Intel chipset Z68), and the corresponding press releases were presented by several companies at once. Although at the time of updating the guide there are simply no video cards with such support, so it's just not interesting. By the time PCIe 3.0 support is needed, completely different boards will appear. Most likely, this will happen no earlier than 2012.

By the way, we can assume that PCI Express 4.0 will be introduced over the next few years, and a new version will also have once again doubled the bandwidth demanded by that time. But this will not happen very soon, and we are not interested yet.

External PCI Express

In 2007, the PCI-SIG group, which officially standardizes PCI Express solutions, announced the adoption of the PCI Express External Cabling 1.0 specification, which describes the standard for data transfer over an external PCI Express 1.1 interface. This version allows you to transfer data at a speed of 2.5 Gb / s, and the next should increase the throughput to 5 Gb / s. The standard includes four external slots: PCI Express x1, x4, x8 and x16. Senior connectors are equipped with a special tongue that facilitates connection.

The external version of the PCI Express interface can be used not only for connecting external video cards, but also for external drives and other expansion boards. The maximum recommended cable length is 10 meters, but this can be increased by connecting the cables through a repeater.

Theoretically, this could make life easier for laptop lovers when using a low-power integrated video core when running on batteries, and when connected to desktop monitor- powerful external video card. The upgrade of such video cards is greatly facilitated, there is no need to open the PC case. Manufacturers can make completely new cooling systems that are not limited by the features of expansion cards, and there should be fewer problems with power supply - most likely, external power supplies designed specifically for a specific video card will be used, they can be built into one external case with a video card using one cooling system. It may be easier to assemble systems on several video cards (SLI/CrossFire), and taking into account the constant growth in the popularity of mobile solutions, such external PCI Express should have gained some popularity.

They should have, but they didn't. As of autumn 2011, there are practically no external options for video cards on the market. Their circle is limited by outdated models of video chips and a narrow selection of compatible laptops. Unfortunately, the case of external video cards did not go further, and slowly died out. You can no longer even hear the victorious advertising statements from laptop manufacturers... Perhaps the capacities of modern mobile video cards have simply become enough even for demanding 3D applications, including many games.

There remains hope for the development of external solutions in a promising interface for connecting Thunderbolt peripherals, formerly known as Light Peak. It was developed by Intel Corporation based on DisplayPort technology, and the first solutions have already been released by Apple. Thunderbolt combines the capabilities of DisplayPort and PCI Express and allows you to connect external devices. However, so far they simply do not exist, although the cables already exist:

In the article, we do not touch on outdated interfaces, the vast majority of modern video cards are designed for the PCI Express 2.0 interface, so when choosing a video card, we suggest considering only it, all data on AGP is provided for reference only. The new boards use the PCI Express 2.0 interface, combining the speed of 16 PCI Express lanes, which gives a throughput of up to 8 GB / s in each direction, which is several times more than the same characteristic of the best AGP. In addition, PCI Express operates at such a speed in each of the directions, unlike AGP.

On the other hand, products with PCI-E 3.0 support have not really come out yet, so it doesn't make much sense to consider them either. When it comes to upgrading an old one or buying new board or simultaneous replacement of the system and video cards, then you just need to purchase motherboards with a PCI Express 2.0 interface, which will be quite sufficient and most common for several more years, especially since products different versions PCI Express compatible with each other.

In this article, we will explain the reasons for the success of the PCI bus and describe the high-performance technology that is coming to replace it - the PCI Express bus. We will also look at the history of development, the hardware and software levels of the PCI Express bus, the features of its implementation and list its advantages.

When in the early 1990s she appeared, then on her own technical specifications significantly outperformed all buses that existed up to that point, such as ISA, EISA, MCA and VL-bus. At that time, the PCI bus (Peripheral Component Interconnect - interaction of peripheral components), operating at a frequency of 33 MHz, was well suited for most peripheral devices. But today the situation has changed in many ways. First of all, the clock speeds of the processor and memory have increased significantly. For example, the clock frequency of processors has increased from 33 MHz to several GHz, while the operating PCI frequency increased to only 66 MHz. The advent of technologies such as gigabit ethernet and IEEE 1394B threatened that the entire bandwidth of the PCI bus could go to serve a single device based on these technologies.

At the same time, the PCI architecture has a number of advantages over its predecessors, so it was not rational to completely revise it. First of all, it does not depend on the type of processor, it supports buffer isolation, bus mastering technology (bus capture) and PnP technology in full. Buffer isolation means that the PCI bus operates independently of the internal processor bus, which allows the processor bus to function regardless of speed and load system bus. Thanks to bus capture technology, peripheral devices can directly control the process of transferring data on the bus, instead of waiting for help from the central processor, which would affect system performance. Finally, Plug and Play support allows automatic tuning and configuring the devices that use it and avoid fussing with jumpers and switches, which pretty much ruined the life of the owners of ISA devices.

Despite the undoubted success of PCI, at the present time it faces serious problems. Among them are limited bandwidth, lack of real-time data transmission functions and lack of support for next-generation network technologies.

Comparative characteristics of various PCI standards

It should be noted that the actual throughput may be less than the theoretical one due to the principle of the protocol and the features of the bus topology. In addition, the total bandwidth is distributed among all devices connected to it, therefore, the more devices sit on the bus, the less bandwidth goes to each of them.

Such standard improvements as PCI-X and AGP were designed to eliminate its main drawback - low clock speed. However, the increase clock frequency in these implementations has resulted in a reduction in the effective length of the bus and the number of connectors.

The new generation of the bus, PCI Express (or PCI-E for short), was first introduced in 2004 and was designed to solve all the problems that its predecessor faced. Today, most new computers are equipped with a PCI Express bus. Although they also have standard PCI slots, the time is not far off when the bus will become history.

PCI Express Architecture

The bus architecture has a layered structure as shown in the figure.

The bus supports the PCI addressing model, which allows all currently existing drivers and applications to work with it. In addition, the PCI Express bus uses the standard PnP mechanism provided by the previous standard.

Consider the purpose of the various levels of organization PCI-E. At the software level of the bus, read / write requests are generated, which are transmitted at the transport level using a special packet protocol. The data layer is responsible for error-correcting coding and ensures data integrity. The basic hardware layer consists of a double simplex channel consisting of a transmit and receive pair, collectively referred to as a link. The total bus speed of 2.5 Gb/s means that the throughput for each PCI Express lane is 250 Mb/s each way. If we take into account the overhead costs of the protocol, then about 200 Mb / s is available for each device. This bandwidth is 2-4 times higher than what was available for PCI devices. And, unlike PCI, if the bandwidth is distributed among all devices, then it goes to each device in full.

To date, there are several versions of the PCI Express standard, which differ in their bandwidth.

PCI Express x16 bus bandwidth for different PCI-E versions, Gb/s:

• 32/64
• 64/128
• 128/256

PCI-E bus formats

At the moment, various options for PCI Express formats are available, depending on the purpose of the platform - a desktop computer, laptop or server. Servers that require more bandwidth have more PCI-E slots, and these slots have more connecting lines. In contrast, laptops may only have one line for medium-speed devices.

Video card with PCI Express x16 interface.

PCI Express expansion cards are very similar to PCI cards, but the PCI-E connectors are more grippy to ensure the card won't slip out of the slot due to vibration or during shipping. There are several form factors of PCI Express slots, the size of which depends on the number of lanes used. For example, a bus with 16 lanes is referred to as PCI Express x16. Although the total number of lanes can be as high as 32, in practice, most motherboards nowadays are equipped with a PCI Express x16 bus.

Smaller form factor cards can be plugged into larger form factor slots without compromising performance. For example, a PCI Express x1 card can be plugged into a PCI Express x16 slot. As in the case of the PCI bus, you can use a PCI Express extender to connect devices if necessary.

The appearance of the connectors various types on the motherboard. From top to bottom: PCI-X slot, PCI Express x8 slot, PCI slot, PCI Express x16 slot.

Express Card

The Express Card standard offers a very simple way to add hardware to a system. The target market for Express Card modules are laptops and small PCs. Unlike traditional expansion boards desktop computers, the Express card can connect to the system at any time while the computer is running.

One of the popular varieties of Express Card is the PCI Express Mini Card, designed as a replacement for Mini PCI form factor cards. A card created in this format supports both PCI Express and USB 2.0. PCI Express Mini Card dimensions are 30×56 mm. PCI Express Mini Card can connect to PCI Express x1.

Benefits of PCI-E

PCI Express technology has gained advantages over PCI in the following five areas:

1. More high performance. With just one lane, the throughput of PCI Express is twice that of PCI. In this case, the throughput increases in proportion to the number of lines in the bus, the maximum number of which can reach 32. An added advantage is that information on the bus can be transmitted simultaneously in both directions.
2. Simplification of input-output. PCI Express takes advantage of buses such as AGP and PCI-X while offering a less complex architecture and relatively simple implementation.
3. Layered architecture. PCI Express offers an architecture that can adapt to new technologies without the need for significant software upgrades.
4. New generation I/O technologies. PCI Express gives you new opportunities to receive data with the help of simultaneous data transfer technology, which ensures that information is received in a timely manner.
5. Ease of use. PCI-E greatly simplifies system upgrades and expansions by the user. Additional formats Express cards such as the ExpressCard greatly increase the ability to add high-speed peripherals to servers and laptops.

Conclusion

PCI Express is a bus technology for connecting peripherals, replacing technologies such as ISA, AGP, and PCI. Its use significantly increases the performance of the computer, as well as the user's ability to expand and update the system.

When we talk about the PCI Express(PCI-E) bus, perhaps the first thing that distinguishes it from other similar solutions is its efficiency. Thanks to this modern bus, computer performance is increased, graphics quality is improved.

For many years, the PCI (Peripheral Component Interconnect) bus was used to connect the video card to the motherboard, in addition, it was also used to connect some other devices, such as a network and sound card.

Here's what those slots look like:

PCI-Express has effectively become the next generation of the PCI bus, offering improved functionality and performance. It uses a serial connection in which there are several lines, each of which leads to the corresponding device, i.e. each peripheral device gets its own line, which increases the overall performance of the computer.

PCI-Express supports "hot" connection, consumes less energy than its predecessors, and controls the integrity of transmitted data. Moreover, it is compatible with PCI drivers- tires. Another remarkable feature of this bus is its scalability, i.e. pci express card plugs in and works in any slot of equal or greater bandwidth. In all likelihood, this feature will ensure its use in the coming years.

The traditional type of PCI slot was good enough for basic audio/video functions. With the AGP bus, the multimedia data processing scheme has improved, and the quality of the audio/video data has increased accordingly. It wasn't long before advances in microprocessor microarchitecture began to further demonstrate the sluggishness of the PCI bus, which made the fastest and latest computer models at the time literally drag on.

Characteristics and bandwidth of the PCI-E bus

It can have from one bidirectional connection line x1, up to x32 (32 lines). The line functions on a point-to-point basis. Modern versions provide much more bandwidth than their predecessors. x16 can be used to connect a graphics card, while x1 and x2 can be used to connect regular cards.

Here's what x1 and pci express x16 slots look like on:

PCI-E
Number of lines x1 x2 x4 x8 x16 x32
Bandwidth 500 Mb/s 1000 Mb/s 2000 Mb/s 4000 Mb/s 8000 Mb/s 16000 Mb/s

PCI-E versions and compatibility

When it comes to computers, any mention of versions is associated with compatibility issues. And, like any other modern technology, PCI-E is constantly evolving and modernizing. Last affordable option pci express 3.0, but the development of the PCI-E bus version 4.0 is already underway., which should appear around 2015 (pci express 2.0 is almost outdated).
Take a look at following table PCI-E compatibility.
PCI-E Versions 3.0 2.0 1.1
Total Bandwidth
(X16) 32Gb/s 16Gb/s 8Gb/s
Data rate 8.0 GT/s 5.0 GT/s 2.5 GT/s

The PCI-E version has no effect on the functionality of the card. The most distinguishing feature this interface is its forward and backward compatibility, which makes it secure and capable of syncing with many card variants, regardless of interface version. That is, you can insert a card of the second or third version into the PCI-Express slot of the first version, and it will work, albeit with some performance loss. In the same way, a PCI-E version 3 card can be installed in the PCI-E slot of the first version of PCI-Express. Currently, all modern video cards from NVIDIA and AMD are compatible with such a bus.

And this is for a snack: