I have been asked this question more than once, so now I will try to answer it as clearly and briefly as possible. To do this, I will provide pictures of the PCI Express and PCI expansion slots on the motherboard for a clearer understanding and, of course, I will indicate the main differences in the characteristics, i.e. .e. very soon you will find out what these interfaces are and what they look like.
So, first, let's briefly answer the question, what exactly is PCI Express and PCI?
What is PCI Express and PCI?
PCI is a computer parallel input/output bus for connecting peripheral devices to the computer motherboard. PCI is used to connect: video cards, sound cards, network cards, TV tuners and other devices. The PCI interface is outdated, so you probably won’t be able to find, for example, a modern video card that connects via PCI.
PCI Express(PCIe or PCI-E) is a computer serial input/output bus for connecting peripheral devices to a computer's motherboard. Those. this already uses a bidirectional serial connection, which can have several lines (x1, x2, x4, x8, x12, x16 and x32) the more such lines, the higher the bandwidth of the PCI-E bus. The PCI Express interface is used to connect devices such as video cards, sound cards, network cards, SSD drives and others.
There are several versions of the PCI-E interface: 1.0, 2.0 and 3.0 (version 4.0 will be released soon). This interface is usually designated, for example, like this PCI-E 3.0 x16, which means PCI Express 3.0 version with 16 lanes.
If we talk about whether, for example, a video card that has a PCI-E 3.0 interface will work on a motherboard that only supports PCI-E 2.0 or 1.0, the developers say that everything will work, just of course keep in mind that the bandwidth will be limited by the capabilities of the motherboard. Therefore, in this case, I don’t think it’s worth overpaying for a video card with a newer version of PCI Express ( if only for the future, i.e. Are you planning to purchase a new motherboard with PCI-E 3.0?). Also, and vice versa, let’s say your motherboard supports version PCI Express 3.0, and your video card supports version 1.0, then this configuration should also work, but only with PCI-E 1.0 capabilities, i.e. There is no limitation here, since the video card in this case will work at the limit of its capabilities.
Differences between PCI Express and PCI
The main difference in characteristics is, of course, throughput; for PCI Express it is much higher, for example, PCI at 66 MHz has a throughput of 266 MB/sec, and PCI-E 3.0 (x16) 32 Gb/s.
Externally, the interfaces are also different, so connecting, for example, a PCI Express video card to a PCI expansion slot will not work. PCI Express interfaces with different numbers of lanes are also different, I will now show all this in pictures.
PCI Express and PCI expansion slots on motherboards
PCI and AGP slots
PCI-E x1, PCI-E x16 and PCI slots
Problems with the PCI-E connector. Power connector, north bridge. Please note that mutant motherboards may not work with all video cards.
ASUS P5Q does not detect video card
Hello. Mother Asus P5Q rev 1.03 starts - on postcard 99 or 98, after 3-5 seconds the posts start running. The speaker gives a signal 1 long 3 short and then posts and a short single signal pass. Naturally there is nothing on the monitor, but Windows is loading judging by the activity of the HDD. There is a picture on the PCI card and the speaker only gives one short signal, although at the start there is still a pause on codes 99 or 98. The BIOS flash drive was replaced and a visual inspection was carried out for mechanical damage. Bridge dump or something else? The video card is 100% working, I even tried several different generations.
Lenovo H81H3-LM board no longer sees PCIExpress16X video card
Good afternoon The Lenovo H81H3-LM board no longer sees the PCIExpress16X video card; it starts normally on the integrated one. The video card is intact and was tested on another PC. On the PCIExpress16X connector - all 12 volts are present, 3.3 too, on the Receiver Lane lines 0.3 volts each, and on the Transmitter Lane 0.1 volts each. I enabled different video priorities in the BIOS, but nothing happened. The connectors in the slot trim are all physically intact. Assumptions 2: either the BIOS is driving, or the socket is dead! I downloaded the BIOS from the manufacturer's website, but it comes as a rom file for the utility. If anyone has it in bin format for proger, I would be grateful.
GA-8I915MD-GV has a FF post, but there is no video signal, both with built-in and PCI-E
Good afternoon, forum members. There is a mother GA-8I915MD-GV, it turns on normally, there is a one-time POST signal, the same status on the pci post card is “FF”, but there is no video signal from the built-in card and from any video card on PCI-E. Accordingly, the wires and monitors were checked and changed.
If you reset the BIOS, loading on the pci post card reaches “7F”, press F1 and then everything is ok “FF” the mother responds to the keyboard.
Visual inspection did not yield any results. Probing for the presence of heated elements also did not give any results. Processes and memories changed.
Tell me where else I can look!?
Thanks in advance, Alexander.
GA-MA770T-UD3
There is a GA-MA770-UD3 motherboard, the speaker swears at Viyukha (.--) in the PCI-e slot. With PCI there is an image and the speaker beeps once as expected (+ the same post 25). I changed the processors, the RAMs too, in different slots. Swap Dual bios; Climbed in the bius; There is voltage on the PCI-e connector, the contacts are fine (ceramic connectors are normal). The voltage on the processor and RAM is normal. What's wrong with her? Is it really a bridge? Gentlemen, pros, tell me what to do! Pliz!
+USB resistance - Ok
Gigabyte GA-M52L-S3P PCI-E not working
Hello! Next problem:
Gigabyte GA-M52L-S3P rev.1.0 starts,
The POST card stops at code 18/88-24 1 - Initialize slot 4. There is no video output on PCI-E (voltages of 3.3V and 5V are present on the connector), the system continues to boot and works if a PCI video card is installed.
I flashed the BIOS, even changed a different chip.
According to the owner, this happened after the case fan was connected incorrectly to the motherboard.
Please tell me what else to measure and check.
Asus M2N-E sorts through video cards
Hi all. Asus M2N-E motherboard.
The gv-rx26p512h video card works fine in this motherboard.
I want to install Asus EN9600GT/HTD/512M/A, but my mother doesn’t see it. Beeps 1 long, 4 short
9600GT is 100% working, it starts normally on another computer.
WiFi modules and other similar devices. Intel began developing this bus in 2002. Now the non-profit organization PCI Special Interest Group is developing new versions of this bus.
At the 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 based on the PCI bus. The main differences between PCI Express and PCI lie at the physical layer. While PCI uses a shared bus, PCI Express uses a star topology. Each device is connected to a common switch with a separate connection.
The PCI Express software model largely follows the PCI model. Therefore, most existing PCI controllers can be easily modified to use the PCI Express bus.
PCI Express and PCI slots on the motherboard
In addition, the PCI Express bus supports new features such as:
- Hot plugging of devices;
- Guaranteed data exchange speed;
- Energy management;
- Monitoring the integrity of transmitted information;
How does the PCI Express bus work?
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 higher the data transfer speed the PCI Express bus can provide. Depending on the number of lines supported, the grade size on the motherboard will be different. There are slots with one (x1), four (x4) and sixteen (x16) lines.
Visual demonstration of PCI Express slot dimensions
Moreover, any PCI Express device can work in any slot if the slot has the same or more lines. This allows you to install a PCI Express card with a x1 connector into a x16 slot on the motherboard.
PCI Express bandwidth depends on the number of lanes and bus version.
|
One way/both ways in Gbit/s |
|||||||
|
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
PCI Express is primarily used to connect discrete video cards. Since the advent of this bus, absolutely all video cards use it.
GIGABYTE GeForce GTX 770 graphics card
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
SSD drive OCZ Z-Drive R4 Enterprise