PCI E 2.0 the same as PCI E 3.0?

[Gixanix]

Hi,

I am hopefully in 2 and a half months time going to be getting a new computer and I was wondering if PCI 2.0 and PCI 3.0 are the same or different. It's very important because i will be getting a R9 270x graphics card which has PCI 3.0 and i don't know if the motherboard i will be getting with allow the card if the motherboard has PCI 2.0 only.

A answer would be helpful thanks :)

[rotNdude]

A video card that is capable of PCI-E 3 will run in a motherboard that is PCI-E 2 and it will run just fine with no performance degradation.

[rojimboo]

PCI-Express is backwards compatible. Your r9 270x will work.

There is a 1% difference in performance between PCI-e 2.0 and 3.0.

http://www.techpowerup.com/reviews/Intel/Ivy_Bridge_PCI-Express_Scaling/24.html

I wouldn't worry about it xd

[Mag]

What rojimboo said is correct, basically the only thing 3.0 provides is more "theoretical" bandwith. From what I can gather is current GPUs do not even use the bandwith 2.0 provides.
Generation | Bit rate | Interconnect Bandwidth | Bandwidth (per lane) | Maximum bandwidth (16 lanes)
PCI-Express 1.1 | 2.5GT/sec | 2GB/sec | 250MB/sec | 8GB/sec
PCI-Express 2.0 | 5.0GT/sec | 4GB/sec | 500MB/sec | 16GB/sec
PCI-Express 3.0 | 8.0GT/sec | 8GB/sec | 1GB/sec | 32GB/sec

http://www.bit-tech.net/hardware/2010/11/27/pci-express-3-0-explained/1

[Gixanix]

Fantastic thanks for the replys now i can get a PCI 2.0 motherboard and not worry about the graphics card having problems :)

[Mag]

At most you would see about 10% boost by having PCIe 3.0, I myself am still using 2.0 and I see no discernible difference. Enjoy!

[_I_]

current gpus are not able to max a pci-e 2.0 x16 slot
the only use for 3.0 is with 2x gpus running at x8+x8