PCI Express x1 vs. x16

[Mofaz]

What is the difference between PCI-E x1 and x16? Speed? Why do some
motherboards have both? What is the use of having one slow speed PCI
slot and one faster PCI slot?

 

[Mofaz]

Also, is PCI good? I saw an ATI 9250 PCI card for a good price. A
lot less than what I've seen. However, the interface was PCI. Not
PCI x1, PCI-Express x16 either. Just PCI.

 

[Paul]

What is the difference between PCI-E x1 and x16? Speed? Why do some
motherboards have both? What is the use of having one slow speed PCI
slot and one faster PCI slot?

There is some info here:

http://en.wikipedia.org/wiki/Pci_express

The x1 slot is intended to be a replacement for a PCI
slot. It has a bandwidth of 250MB/sec in each direction,
and the interface is bidirectional.

The x16 slot is intended as a replacement for the AGP
slot. It has a bandwidth of 4000MB/sec in each
direction, and the interface is bidirectional.

One difference about x16 PCI Express, is there is no
GART as in AGP. The x16 PCI Express slot can be
used for video cards, but it can also be used for
RAID controllers or 10GbE network interfaces. So the
function of the PCI Express slots is not fixed. (For
example, there are even video cards from Matrox
that plug into a PCI Express x1 slot.)

Just recently, a format for PCI Express cabling has been
approved, so now it is possible to extend the lanes
via cables. So someday, you may be seeing PCI Express
used to extend I/O bandwidth, outside the computer.

"PCI Sig approves external cabling spec 1.0"
http://www.theinquirer.net/default.aspx?article=37528

Paul

 

[Mofaz]

Thanx, Paul.

There is some info here:

http://en.wikipedia.org/wiki/Pci_express

The x1 slot is intended to be a replacement for a PCI
slot. It has a bandwidth of 250MB/sec in each direction,
and the interface is bidirectional.

The x16 slot is intended as a replacement for the AGP
slot. It has a bandwidth of 4000MB/sec in each
direction, and the interface is bidirectional.

One difference about x16 PCI Express, is there is no
GART as in AGP. The x16 PCI Express slot can be
used for video cards, but it can also be used for
RAID controllers or 10GbE network interfaces. So the
function of the PCI Express slots is not fixed. (For
example, there are even video cards from Matrox
that plug into a PCI Express x1 slot.)

Just recently, a format for PCI Express cabling has been
approved, so now it is possible to extend the lanes
via cables. So someday, you may be seeing PCI Express
used to extend I/O bandwidth, outside the computer.

"PCI Sig approves external cabling spec 1.0"http://www.theinquirer.net/default.aspx?article=37528

Paul

 

[Damaeus]

In "Mofaz" <[email protected]> posted

What is the difference between PCI-E x1 and x16? Speed? Why do some
motherboards have both? What is the use of having one slow speed PCI
slot and one faster PCI slot?

I was doing some research earlier today and found that a video capture card
has been released for the PCIe x1 slot. Supposedly it has better data
transfer rates than the regular PCI slot.

I, for one, hope to see more PCIe x1 cards coming out, like a new
Soundblaster solution. The system I just built only has one PCI slot and
it's killing me. I should have gotten a different motherboard.

Damaeus
--
Motherboard Abit Fatal1ty AN9 32X
Processor AMD Athlon 64 X2 4200+ Dual Core
Graphics nVidia GeForce 7950GTOC
Memory 2GB DDR2 800 PC6400
Hard Drives 2x 320GB Western Digital SATA

 

[DaveW]

The PCI-E x16 slot is for the video card in the system. The x1 slots are
for future non-video devices which will NOT require x16 speed.