• Some users have recently had their accounts hijacked. It seems that the now defunct EVGA forums might have compromised your password there and seems many are using the same PW here. We would suggest you UPDATE YOUR PASSWORD and TURN ON 2FA for your account here to further secure it. None of the compromised accounts had 2FA turned on.
    Once you have enabled 2FA, your account will be updated soon to show a badge, letting other members know that you use 2FA to protect your account. This should be beneficial for everyone that uses FSFT.

Tri-Crossfire: 5970+5870. How?

StormClaw

StormClaw

Gawd
Joined
Jun 10, 2009
Messages
565
What are the requirements to Tri-Crossfire 5970+5870 ?

- do both cards have to be from the same manufaturer?
- do both cards need to have same memory? (5970 2Gb + 5870 2Gb)
- do both card need to run at the same speeds? (OC 5870 vs non-oc 5970)

:confused:

sorry, but i'm a total ATi noob
 
5970's RAM is split between both GPUs; you'd need a 4GB 5970 to use a 2GB 5870. You can mix, but you'll lose memory that isn't available to both cards, IIRC.

I don't think manufacturer matters; speeds need to be the same in Crossfire.
 
If the speeds aren't the same in crossfire it will down clock all cards down to the lowest common denominator as in your 5870 will clock down to 5970 clocks.
 
Are HD5970 4GB versions available yet?

I think HD5970 2GB + HD5870 1GB is the only viable option atm.
 
SixtyWattMan said:
If the speeds aren't the same in crossfire it will down clock all cards down to the lowest common denominator as in your 5870 will clock down to 5970 clocks.
Click to expand...

I'm not 100% on the up and up on crossfire, but I know this is a very common misconception with SLI as it does not downclock cards. I'd assume the same would be true with crossfire.
 
They use lowest common denominator approach for both memory and speed, so you need to clock your 5970 to 5870 clock speeds to make full use of the setup and also use cards with equivelent memory, remember that the 5970s memory is shared between each core so you need to half that for comparisons sake (2gb becomes 1gb per gpu, 4gb becomes 2gb per core)

You can mix and match brands.

On a personal note, I dont think the 4gb 5970s will be worth it, nor the 2gb 5870, and 5970s clock to 5870 speeds no issue, need a slight vcore bump, use MSIs Afterburner for that.
 
PrincessFrosty said:
They use lowest common denominator approach for both memory and speed, so you need to clock your 5970 to 5870 clock speeds to make full use of the setup and also use cards with equivelent memory, remember that the 5970s memory is shared between each core so you need to half that for comparisons sake (2gb becomes 1gb per gpu, 4gb becomes 2gb per core)

You can mix and match brands.

On a personal note, I dont think the 4gb 5970s will be worth it, nor the 2gb 5870, and 5970s clock to 5870 speeds no issue, need a slight vcore bump, use MSIs Afterburner for that.
Click to expand...

i think i'm gonna wait for the 4gb 5970 Toxic and pair it with a 2gb 5870 Toxic

:eek:
 
StormClaw said:
i think i'm gonna wait for the 4gb 5970 Toxic and pair it with a 2gb 5870 Toxic

:eek:
Click to expand...

What resolution are you going to power with that?

It's a waste of money unless you have more than about a > 4Mpix screen, that basically means eyefinity with 3x 22" or above.
 
PrincessFrosty said:
What resolution are you going to power with that?

It's a waste of money unless you have more than about a > 4Mpix screen, that basically means eyefinity with 3x 22" or above.
Click to expand...

2500 x 1600 (30" dell)

right now my GTX 285 SLI are barely cutting it


maybe upgrade to 3x24" when they fix the eyefinity bugs
although 3x30" would be sex (however i doubt that the cards would keep up)
 
*pair a 1GB 5870 with a 2GB 5970*
*overclock the 5970 to 850/1200*
*cry when half your games stutter at 2560x1600 with even 4x AA*
*sell the trifire and buy a pair of GTX 480*

That's how I did it anyway. At least I didn't lose any money on the ATI cards.
 
anonmoniker said:
Not enough memory.



The 480 has no crashing problem. Google 5870 gray screen if you want to hear about a crashing problem.
Click to expand...

GSOD = Hardware defective issue.

480 so far with latest driver crash me every time when I play some game, like DiRT 2 multiplayer, SC2, SF4 .. it crash randomly and starts getting annoying.
btw, this is without OC. my OC is table as hell, burn through furmark for 2 day.
also, it doesn't happen to any other game that I play with only those few..
 
StormClaw said:
They would also turn your PC into a furnace and make it sound like a jet runway.

I'm willing to trade some speed in favor of much cooler temps and much less noise.
Click to expand...

Nah, the temps and heat of Fermi turned out to be a non-favtor.

And the HD5970 is plenty hot.

THe only thing to consider is power uage, but still, I would go Dual 480 here.

But thats just Bob, you do what you have to do.
 
shansoft said:
GSOD = Hardware defective issue.

480 so far with latest driver crash me every time when I play some game, like DiRT 2 multiplayer, SC2, SF4 .. it crash randomly and starts getting annoying.
btw, this is without OC. my OC is table as hell, burn through furmark for 2 day.
also, it doesn't happen to any other game that I play with only those few..
Click to expand...
If you literally ran Furmark for 24/7 for 2 days, I wouldn't be surprised if you damaged your card. That program is pretty unsafe, I watched it cook the VRMs on my old GTX280 to over 120* C. Gaming in Crysis was nowhere near those temperatures. I wouldn't recommend running Furmark for any stretch of time..
 
Rizen said:
If you literally ran Furmark for 24/7 for 2 days, I wouldn't be surprised if you damaged your card. That program is pretty unsafe, I watched it cook the VRMs on my old GTX280 to over 120* C. Gaming in Crysis was nowhere near those temperatures. I wouldn't recommend running Furmark for any stretch of time..
Click to expand...

huh... not literally, I actually did it to see if I am stable @ 860/2000.. and it does..

the fan was on 100% all time..

and the crash issue only occur in those game that I play with, but not to others.
which is the odd part if its really burned....

I also have exact same issue with my old 8800 GTX on latest driver, but not the 186 or lower... which pretty much prove my point there..
 
bastage said:
wouldnt a 5970 pair up to a 5850 better then a 5870?
Click to expand...

I would say tri-fire 5870 would be better overall..

5970 isn't up to my expectation to be honest.. even same clock as 5870, still lose to 5870CF. not quite sure why.. probably PCIE bandwidth..
 
bastage said:
wouldnt a 5970 pair up to a 5850 better then a 5870?
Click to expand...

At stock, yes.

However the 5970 is actually 5870 hardware so has no problem running at 5870 speeds (and above), it's just been clocked down to keep power draw under 300W. I would say anyone with a 5970 that isn't running at 5870 speeds is wasting a good card.
 
shansoft said:
I would say tri-fire 5870 would be better overall..

5970 isn't up to my expectation to be honest.. even same clock as 5870, still lose to 5870CF. not quite sure why.. probably PCIE bandwidth..
Click to expand...

Canned benchmarks show this but [H] gameplay evaluations don't show it. I haven't seen anyone really review a 5970 @ 850/1200 speeds vs 5870 CFX.

http://www.hardocp.com/article/2010/04/12/ati_radeon_hd_5870_eyefinity_6_performance_review/4

This BC2 performance snippet tells me that, with avg fps within 8 and mins within 4, overclocking my 5970 to 850/1200 should get me exactly the same performance for $100 to $300 less than 5870 crossfire at Eyefinity resolutions.

Similar results were shown with Metro. Bottom line is that there isn't enough shader power to run AA on the newest DX11 games, and for older engines such as bc2.. who can tell the difference between 4xAA and 8xAA at 5760?
 
dook43 said:
Canned benchmarks show this but [H] gameplay evaluations don't show it. I haven't seen anyone really review a 5970 @ 850/1200 speeds vs 5870 CFX.

http://www.hardocp.com/article/2010/04/12/ati_radeon_hd_5870_eyefinity_6_performance_review/4

This BC2 performance snippet tells me that, with avg fps within 8 and mins within 4, overclocking my 5970 to 850/1200 should get me exactly the same performance for $100 to $300 less than 5870 crossfire at Eyefinity resolutions.

Similar results were shown with Metro. Bottom line is that there isn't enough shader power to run AA on the newest DX11 games, and for older engines such as bc2.. who can tell the difference between 4xAA and 8xAA at 5760?
Click to expand...

I have only tried it with 10.3 driver, don't know if 10.4 change anything.
but from my old test, 5870CF was running better in Crysis/WARHEAD than 5970, less stutter. For Metro 2033, IIRC, it was 2-3fps higher in Library part, since it was the only part that I did the test.
 
You must log in or register to reply here.
Back
Top