Does SLI require 2 identical cards?

[Raphie]

When looking at the Nvidia website it says that you need 2 SLI certified cards (not stating that these have to be identical) I have a XFX 7800GT and a XFX 6800, if i do the SLI mod for my Ultra-D AND find a SLI bridge somewhere, will this combo then work?

 

I would like to test it myself, but i already spend 4 hours yesterday on replacing my DFI chipset fan with a Zalman cooler (motherboard on a tray ) and i am not the solder king.

 

Before dedicating another weekend to my PC, i would to know if this will work. Does anybody also have an expectation on performance gain? currently running 3Dmark05 at nearly 8600 points.

[the_vandyl]

nope

the ATI's do it but it bumps it down to the lower boards pipeline

[Guest fox]

i no its a long shot, but has anyone tested using a higher spec'd card with a lower spec'd card by using rivatuner to underclock so their matched and disable any extra pipelines? possibly on ultras/gts/nus but im guessing no chance in hell of a 7800+6800.

sensible use? you bought a 6800GT, couldn't get one now, so you disable a quad and a VS and sli it with a 6800GS of same clock speeds. and im guessing due to ROPs you may have problems with this

[the_vandyl]

different bios

[NEOAethyr]

It's supposed to be possible with totally diffrent crds, nvidia wise, with the newer drivers but I woud'nt really know.

 

As for somewhat identical cards, ie 2 gf7's.

If it does'nt work, make a bios for them, and flash it to both the cards.

Should work unless... , ie the hardware vendor id can't be changed it seems even though you can force the bios part of it.

 

Would probably work though.

I think, I have'nt checked to see if the driver looks for the hardware version of the vendor id.

 

In any case try using the newest driver possible, ie from nv's ftp.

 

ftp://download1.nvidia.com/Windows/Quadro_Certified/

 

Back up one dir to get into the normal consumer drivers.

81.98 is'nt out yet for some reason, been like that all day.... ^^

 

Edit:

I suppose it's possible to doit it even if the driver does look at the hardware vendor id.

You can force the driver to detect a quadro and work, but it's still a fake quadro ie like rivatuner's crappy nvstrap thing.

Well you need both rt's nvstrap and the little work around by modding the inf(not just swapping the id's).

 

It's a little odd.

 

You need to force a quadro as a gefore and a geforce as a quadro, or somehting I can't remmember, lemme see if I can bring it up.

 

This is'nt really known out there in the public though..., ohwell I have no need for it anymore, since the newer protections of the newer cards.

 

I thin this is the correct way, I can't remember, I'd have to doit again.

 

Edited out, was the wrong one and I don't have to test to find the correct way.

 

It forces the quadro as a geforce, you install the quadro though instead.

When it falls back, well it works.

It gets the cpl to recognize it's a quadro all out except for the ogl.

If you cobine with rt's nvstrap, it makes a full fake quadro, but still protections are in place in ogl apps and will go into a inf loop sometimes.

 

Plus, a real quadro's performce is a bit diffrent.

None the less, this still gets rid of macrovision protection when doing caps lmao .

 

The performance diffs with this is quite alike with a real quadro, but liek I said it's a tad bit diffrent.

 

Also newer cards, the driver knows that it's not real.

So there's no preformance benifits, or rendering benifits at all.

 

I have'nt check macrovision at all though in the newer cards.

 

Another thing is tr'v nvstrap sets up totally wrong strap device id's, so that does'nt help.

Ie a qfx 540, it's strap device id is 0000h, while rivatuner sets it up as 014e lol.

 

Nvstrap is still not a real quadro anyways, /me must find the hardware id maps for the 6600gt ref pcb.....

(I think I know where they are but I dn what is what).

 

 

Sorry about getting so off topic.

 

 

Another edit:

The above inf thingy was wrong anyways...

I can't remember where I have that located right now.

So I'm gonan take it out, makes me look stupid.