8 replies to this topic

[Luke Garrad]

Maybe buying Radeon HD 7850. But its PCI E 3.0. Will it be backwards compatible in a 2.0 slot?

Also has anyone had experience with this card on Mech Warrior. How well can it run?

[Raven-kell]

yes it will work, 3 will work in 2.1 2.0 they are backwards matching.

[Sen]

Is compatible with PCIE 2.0, will run at 2.0 speeds, which is not an issue as it's . . difficult to even come close to maxing out PCI-E 2.0 lanes, to say nothign of 3.0.

I can't help with the 7850, I have two 7950, but I CAN say the game is fairly CPU heavy right now, so if you're running a dual core processor I wouldn't expect miracles.

If you're running an intel core i5/i7 or quad core + AMD, you should be ok.

[Aznpersuasion89]

i am currently running a 7850 with 2.0 slots. no problems

[Sir Roland MXIII]

The "version" number for PCI-Ex doesn't mean much. Putting a video card that's lower or higher PCI-Ex than the motherboard will:
1- Always work, and
2- Never effect performance in a manner the mark one eyeball would ever be able to notice.

Edited by Sir Roland MXIII, 22 January 2013 - 06:22 PM.

[Bad Karma 308]

______________________________________________________________________________________
From PCI-SIG, the special interest group responsible for PCI Express, published PCI-E x.x specifications

PCI-E 1.0 per-lane data rate of 250 MB/s and a transfer rate of 2.5 gigatransfers per second (GT/s).

PCI-E 2.0 doubles the transfer rate compared with PCIe 1.0 to 5 GT/s and the per-lane throughput rises from 250 MB/s to 500 MB/s. This means a 32-lane PCIe connector (×32) can support throughput up to 16 GB/s aggregate.

PCI-E 3.0 can "achieve bandwidth near 1GB/s in one direction on a single-lane (x1) configuration and scale to an aggregate approaching 32GB/s on a sixteen-lane (x16) configuration."

PCI-E 4.0 PCI-SIG announced PCI Express 4.0 featuring 16 GT/s, still based on copper technology. Final specifications are expected to be released in 2014/2015
_____________________________________________________________________________


I believe that both Maximum PC and AnandTech did some studies awhile back on the PCI-E version and how bandwidth affects overall GPU performance. If I remember right, the extra bandwidth and aggregated pipelines only really benefited the highest GPU at the time, want to say it was roughly the Nvidia 480 and ATI 4870 and their dual GPU brethren time frame.

The charts reflected that some high performance card do perform slightly better when offered the higher bandwidth, but the differences were negligible. It's really more about de-cluttering the data flow across more aggregated pipes.

Judging by the specs you'd only see a drastic impact is if you put a 3.0 card into an old 1.0 spec MB.

I have a few pieces of hardware at work that will completely saturate a x16 lane PCIE-3 bus, but it's not hardware you'd ever encounter outside of enterprise class equipment.

So stick with Rolands advice on this

Edited by Bad Karma 308, 22 January 2013 - 07:32 PM.

[OmegaNull]

The motherboard will automatically set the PCIe slot to PCIe 2.0. In short, your card will work fine.

[Burned_Follower]

Luke Garrad, on 22 January 2013 - 04:57 PM, said:

Maybe buying Radeon HD 7850. But its PCI E 3.0. Will it be backwards compatible in a 2.0 slot?

Also has anyone had experience with this card on Mech Warrior. How well can it run?

I was wondering the same thing. I got an ASUS radeon 7950 oc and it's a 3.0 card. I have one 3.0 slot on my MB and 2.0 slots as well. Just out of curiosity, i tested MWO with my GPU in each slot and i got absolutely ZERO difference in performance. Hope that helps.

[Corvus Antaka]

I shifted to an HD7870 with a SSD for the boot/gaming drive. Still on my Dual Core. It has helped significantly, I can run the game at high-ultra high now. However with the most recent patch ive lost some FPS again, though hopefully in the future this will come up again.

Still, with a high end dual core it is possible, I dont drop below 18FPS hardly ever anymore, and even then its pretty smooth compared to before.

I can definitely recommend the 7850+, very nice video card, esp if you run super high 1080p resolutions.