7870XT/7950 crossfire

kevovek

I've been tinkering with clocks and voltages for 2 days now and I still can not get it to stop crashing as soon as benchmarks or games launch.
I cant find anything online about someone with a similar set up (although maybe I'm looking in the wrong places) so I thought I'd ask here to see if by chance anyone has experience in crossfireing two different cards.
set up is:

FX6300 @4.4
asrock 970 pro3
Sapphire 7950 vapor X in the x16 slot
Club 3D 7870XT in the x4 slot

kevovek

I'm at my wits end with this crossfire set up haven't been able to play a game with it for a few days and can't find an answer online or otherwise that fixes it, only thing I haven't tried is clocking the cpu back to stock

kaimera

Last time I tried to CF two diff cards was a 48xx series and machine wouldn't boot with both.

fyi

CrossFire can be implemented with varying-GPU cards of the same generation (this is in contrast to Nvidia's SLI, which generally only works if all cards have the same GPU). This allows buyers who have varying budgets over time to purchase different cards and still get the benefits of increased performance. With the latest generation cards, they will only crossfire with other cards in their sub series. For example, GPU in the same series can be crossfired with each other. So a 5800 series GPU (e.g. a 5830) can run together with another 5800 series GPU (e.g. 5870). However GPUs not in the same hundred series cannot be crossfired successfully (e.g. a 5770 cannot run with a 5870).

kevovek

7870XT and 7950 can definitely be crossfired though and it was even working for me at one stage. I'm going to put all my afterburner/ccc settings up here later to see if anyone can spot anything. I've probably made a simple error and will feel stupid but relieved when its sorted.

kevovek

Here is all my CCC and afterburner settings

ED E

kevovek wrote: »

7870XT and 7950 can definitely be crossfired though and it was even working for me at one stage. I'm going to put all my afterburner/ccc settings up here later to see if anyone can spot anything. I've probably made a simple error and will feel stupid but relieved when its sorted.

I suspect it wasnt actually crossfiring.

AMD says no can do:

kevovek

The 7870XT uses the same tahiti chip as the 7950 so it basically a crippled 7950 card it cant crossfire with a standard 7870 only a 7870XT or a 7950
http://www.techpowerup.com/gpudb/1860/radeon-hd-7870-xt.html

kevovek

A complete amd driver wipe did the trick for me in the end but I'm still none the wiser as to what I did to cause a problem in the first place as it was working originally. It was nearly impossible to find anyone with the same set up on various forums obviously not a popular choice for crossfire. I'm in the process of overclocking the 7870XT now to get the maximum performance out of both cards

BloodBath

I assume you have the 7870xt on the bottom then. It should run a little cooler there and overclock a little higher.

kevovek

Yeah I've got it in the second slot both cards are staying below 60 at the moment. I have a fan on the bottom of the side panel of my case that's bringing air in on top of both the cards so I reckon that's definitely helping