Whats the story with SLI

MooseJam

Giving a little thought to buying a second 8800GT, so whats the story with SLI, can the two cards be different brands but just the same modal or do the two cards have to be identical ? what about the same modal ie 8800gt but different brands and different clocks too ? if I bought a second card I'm assuming it would come with a connector to join the two ? I'd have to get a new motherboard and probably a new power supply too, I don't think I have two of those 6 pin yokes you plug into the graphics card, maybe maplin have a molex to six pin converter

Grim.

only really need it if your running games at mad resolutions tbh

Jamtoast

All i knowabout SLI is that the 2 graphics cards should be the exact same in clockspeeds memory etc but in not sure about brands, but if you are happy with the brand you have now well buying another one of the same would make sence. and like the other reply SLI is for very high settings, but i think that anyone wanting to play games would want awesome graphics + performance soif ya have the money you might as well go SLI GT's

Conar

Don't worry Moose I'm not following you

Check out Nvidia's slizone (http://forums.slizone.com/index.php?showtopic=4776)

Q: Can I use two different video cards in SLI?
A: Not unless the cards meet the requirements for SLI: both cards must be of the same family and model, but nearly everything else can either be compensated for (such as clock speeds) or does not have to be similar (VGA BIOS versions, manufacturers, etc.) For example, an 8600 GTS and a 7600 GT couldn't be used in SLI because they differ on both levels. If you have a card, say an EVGA 7900 GS, that you bought some time ago but want to combine with an ASUS 7900 GS you just bought, then there shouldn't be any problem.

Q: Can I have two cards with different speeds/memory amounts in SLI?
A: Of course! It'll just take a little extra work. When there is a discrepancy between two graphics cards' specifications (for example, GPU clock) you have one of two options: install the slower card in the primary PCI-Express slot or install the faster card in the primary slot. Setting the slower card as the master automatically underclocks and adjusts the speeds of the faster card to match that of the less fortunate card, which keeps them in step. When you set the faster card as the master, the slower card gets its speeds beefed up to that of the master card. Doing this can cause system instability, visual artifacts, higher GPU temperatures and sometimes component failure, so only do this when the cards can handle it (third-party cooling, excellent air circulation and only moderate differences between the speeds.) The same goes for memory speeds, not just GPU speeds, in case there were any questions. Now, this is not the same when the memory sizes of the two cards differ, such as the 8800 GTSs or the 7800 GTXs. When one card has more VRAM than the other, the card with less memory has to be installed in the primary PCI-Express slot to run SLI. Additionally, you will need to change the CoolBits registry string and change its value to 18. This automatically disables a certain amount of memory banks on the other card, making all things equal between them. This can't work in the other way because, well, you can't just magically create memory banks, as nice as that would be.

So they don't need to neccesarily have the same clock speeds.
I haven't done this though so you may want to look into it a little more before taking the plunge.

A mate has an XFX and an MSI 8800GT running in SLi at the moment.
He reckons it meant the difference in 3dmark06 score of circa 10000 to circa 13000

MooseJam

Thanks for the info, thats everything I wanted to know, though I'm kinda going off on the idea, I'm thinking it would be a bit too expensive, new board + power supply + card could be the guts of 500 quid. I have an XFX 8800GT myself and my 3dmark06 score is 14266 so I don't really need a boost, thats what I'm telling myself lol be sensible

RoyalMarine

wait until the summer when the crysis killer graphic cards are around for a while. they will drop in price and so will the 8800gts.
then it might be more affordable to get it.

14266 is a **** load more than most people get.
unless you really have cash to burn its not worth it.