6970, should I trifire?

[Dale]

Interested to hear thoughts on trifire 6970's?

I'm getting some second hand 6970's off a mate, he has x2 in CF currently, both watercooled. Wondering what the gains / potential would be if I added a third to the equation?

I want to game in Eyefinity (5760x1200) - mainly play BF3.

Anyone done the above? How do they scale?

Thanks.

 

[Rusty0611]

Third cards never really scale THAT well. But if you can get one cheaply, why not?

 

[johny dolan]

I got a good boost in most games when i added a 6970 to my 6990 and you will get same kind of performance as sli 680

 

[mrflibbleuk]

I got a good boost in most games when i added a 6970 to my 6990 and you will get same kind of performance as sli 680

Do you have to nail your pc to the floor to stop it taking off?

 

[Dale]

Cool - cheers guys, was just checking mainly that it wasn't an utterly pointless idea. Get low to high 50's with x3 monitors on medium in BF3. Be nice to chuck that up to high, or even ultra with the 3rd card in play?

Just wondering if anyone has actually got trifire 6970's that could comment?

 

[Saul]

I assume you have dual 6970's at the moment? What's your total resolution with all 3 monitors then? Also what FPS do you get on Ultra on BF3?

It would be very useful for me to know this as I'm considering dual crossfire of 6950s, and mainly play BF3.

Thanks in advance man

 

[Surveyor]

This might help: Micro-Stuttering And GPU Scaling In CrossFire And SLI

The performance of three- and four-way CrossFire setups not only surprised us, but also managed to utterly convince us that micro-stuttering doesn't have to affect your multi-GPU configuration. For some reason, the third GPU almost always eliminates micro stuttering and has a less-pronounced effect on performance.

Do you have a motherboard that will allow TriFire with ideally at least x8 speed on the PCI-E slots for each card?

Do you have processor that isn't going to be a bottleneck?

Do you have a suitable PSU with 3x6 pin and 3x8 pin PCI-E power connectors (assuming they're not 2x8 pin cards)?

i7-2600K @ 4.6GHz
TriFire unlocked HD 6950 Sapphire TOXIC's @ 980MHz/5400MHz

Prime95 running 8 threads, CPU @ 100% load
Furmark running all 3 GPU's @ 95%+ load

Maximum power draw from the mains 850W.

1250W Gold rated PSU, say 92% efficient.

Actual output from the PSU ~782W.

 

[Dale]

I assume you have dual 6970's at the moment? What's your total resolution with all 3 monitors then? Also what FPS do you get on Ultra on BF3?

It would be very useful for me to know this as I'm considering dual crossfire of 6950s, and mainly play BF3.

Thanks in advance man

Total resolution is 5760 x 1200 on x2 Dell 24" monitors (x2 2405FPW and x1 U2410)

Not sure on Ultra, but on High we just tried Caspian 64 player and averaged high 30's to low 40's.

This might help: Micro-Stuttering And GPU Scaling In CrossFire And SLI



Do you have a motherboard that will allow TriFire with ideally at least x8 speed on the PCI-E slots for each card?

Do you have processor that isn't going to be a bottleneck?

Do you have a suitable PSU with 3x6 pin and 3x8 pin PCI-E power connectors (assuming they're not 2x8 pin cards)?

Motherboard is a Gigabyte P67AUD7
Processor is a Sandybridge 2600K 3.4
PSU: I currently have an oldish 850w Zalman - this I realise I will have to replace.

Cheers

 

[Surveyor]

Nice motherboard.

I use the Asrock Z68 Extreme7 which allows better spacing between the cards if air cooling.

You'll be wanting to overclock that CPU if you haven't already.

 

[Dale]

Thanks

Annoyingly we tried to overclock, just a mild bit (3.8 - 4ghz) and whilst stable in Windows it eventually always ended up bluescreening when gaming.

Overclocking will be another topic another day (interesting link on Micro stutter by the way - thank you for that)

The whole system is watercooled already - temps are very low.

 

[BoozerDawg]

No harm in tri'ing.

 

[Dale]

No harm in tri'ing.

Fabulous hehe

 

[Dale]

Would anyone recommend a PSU for x3 6970's?

This is what I'm thinking:

OCZ ZX Series 1000W '80 Plus Gold' Modular Power Supply