7800GTX SLi problem

[matt1]

Not really a problem as such but I currently have a XFX 7800GTX @ 450 (pre-overclocked) and my dad has just upgraded to 8800GTXs so he has give me his two Club 3D 7800GTXs (clocked lower by default, 400,420?).

Now I know there was a driver update a while back that allows different branded cards to be used in SLi, even different BIOS versions. I'm tempted to see which Club 3D card clocks the best and clock it up to 450MHz and run it in SLi with my XFX card, but if it will cause issues I'd prefer just to use both Club 3D cards. Basic question is, do I sell an XFX card or a Club 3D card?

Cheers for any input.

 

[MeatLoaf]

Any 2 cards can be used with newer drivers, as long as they have the same core, so any of yours should work perfectly.

The cards run at the speed of the card in the upper slot, so if you put the xfx at the top and the club 3d in the bottom, both will run at the same overclocked xfx speed

Personally id use the 2 club 3d cards, mainly because id prefer to have 2 the same. Just down to personal choice really.

 

[Bomag]

The default clock for a 7800gtx is 430Mhz. Unless nVidia have changed the latest drivers the speed will be the lower setting on either card so 430+1250 and 450+1230 should give 430+1230. You can always use coolbits to overclock.

 

[MeatLoaf]

Nope ive used sli a few times and they definatly run at the speed of the top card.

I had a bfg 7800GT OC then added a galaxy standard 7800GT and they ran at the BFG settings.

 

[matt1]

Thanks for the replies guys, new to SLi myself although I've set it up for people (only identical cards). My main question is whether I keep or sell the XFX card. As a brand I suppose there isn't an immense amount of difference, and it may be better to keep identical cards for SLi, but it's just that the XFX card is pre-overclocked higher and therefore I'm lead to believe the core was selected from a better batch (450Mhz opposed to 430MHz).

I've run the Coolbits auto-detect feature on both the Club 3D cards (individually) and get 490-491MHz on both, got a feeling that Coolbits will only suggest values in a safe range (so no difference between them to note). Wish they designed a Nvidia-Tool to do it like the ATI version!

The reference cooler on both cards is the same but the XFX card has the nice metal bar on the side. Bah, choices.

 

[Duff-Man]

Nope ive used sli a few times and they definatly run at the speed of the top card.

I had a bfg 7800GT OC then added a galaxy standard 7800GT and they ran at the BFG settings.

Odd...

I had SLI 7800GTXs and this wasn't the case. I had a Gigabyte which was clocked at 430mhz stock (but would overclock to 500mhz no problems), and a BFG card which was clocked at 460mhz stock (and would reach about 480 stable). I had the gigabyte as the primary as it had better clocking potential, and both cards defaulted to the 430mhz stock.

I guess, then, the answer is that the cards will run at the stock speeds of the primary card?

Anyway, to answer the question of the OP there is no need for BIOS updates etc these days, the drivers will handle the different card brands without issue.

 

[Emlyn_Dewar]

got a feeling that Coolbits will only suggest values in a safe range (so no difference between them to note). Wish they designed a Nvidia-Tool to do it like the ATI version!

You can use Ati Tool with nvidia cards.
Careful with Coolbits, when I used it with my 6800GS it suggested a ridiculous memory speed, artifacts galore...

 

[MeatLoaf]

Odd...

I had SLI 7800GTXs and this wasn't the case. I had a Gigabyte which was clocked at 430mhz stock (but would overclock to 500mhz no problems), and a BFG card which was clocked at 460mhz stock (and would reach about 480 stable). I had the gigabyte as the primary as it had better clocking potential, and both cards defaulted to the 430mhz stock.

I guess, then, the answer is that the cards will run at the stock speeds of the primary card?

Anyway, to answer the question of the OP there is no need for BIOS updates etc these days, the drivers will handle the different card brands without issue.

Thats what i said They default to the clock speed of the top card

 

[matt1]

You can use Ati Tool with nvidia cards.
Careful with Coolbits, when I used it with my 6800GS it suggested a ridiculous memory speed, artifacts galore...

Yes but not the overclocking feature, only the stress test thingy-ma-bob. Unless there is a newer version?

 

[Duff-Man]

Thats what i said They default to the clock speed of the top card

Ah, sorry I read it wrong. I though you meant 'top-clocked card'. All makes sense now!

 

[Bomag]

In the three different SLI set-ups I have dealt with it has always set the speeds to the lowest level. However, this could be dependent on the MB used.