Is there any advantage using two 512mb graphics cards over one 1Gb card?

Say for example you had two 512mb SLI graphics cards, would that be faster, better than just having a single 1gb graphics card? Assuming they're the same in terms of spec in every way, i'm just wondering if dual cards work like dual processors and increase performance not only because of their size but the fact there're two of them.

Is there any advantage using two 512mb graphics cards over one 1Gb card?
Yes it would be faster because of the dual gpu's, not because of the RAM. It may not be much faster though, and it could very much be overkill. Many cards can max out every setting by themselves, and other times dual cards only increase performance when running extremely high resolution, and then only a little sometimes. If you look around at benchmarks for dual setups, many times they only increase performance by 10-15%. I know for sure that a single 8600gt is way more pwerful than two 8400's, and the 8800gts is much much more powerful than two 8600's.


The amount of RAM doesnt have much to do with general performance, but it does effect overall.


A slow gpu with alot of RAM will suck, but a powerful gpu with only a small amount of RAM could be literally several times more powerful.


The great thing about modern cards is that they can use system RAM in addition to the onboard, and man can it make a difference.


I have a laptop with the ATI x1600 128mb with hypermemory (fancy word for shares system RAM) and the amount of system RAM allocated makes a huge difference.


When I had 1gb of RAM there was no system RAM allocated for the card, and my games suffered. In BF2 I only got 1-2fps on highest settings, but as soon as I upgraded to 1.5gb RAM the system allocated an entire 512mb of system RAM and now BF2 plays at anywhere from 45-60 fps on highest settings. Now that I upgraded to 2gb, it has 763mb of RAM allocated, and it runs freakin awesome.


After my experience with this card, I would not hesitate to go with a card with lower RAM as long as I had extra system RAM. The savings could be significant. A gb of RAM is less than $50, but most cards with alot of RAM are more than that, just look at the difference in price between the low RAM 8800 series and the high RAM versions, its $200 in some cases.
Reply:If they had the same GPU core then you would get a speed advantage using SLi, but that can depend on the drivers you use.
Reply:2 GPUs are faster than 1 GPU. It isn't just about the video memory...





"i'm just wondering if dual cards work like dual processors and increase performance" - Absolutely right!!!
Reply:they all use the same buses , so makes no odds about if they are on 1 / 2 ports. as said before.. more about the gpu's





so say you had ONE card that supported 2 gpu chips, would be fast..





SLI doesn't warrent me getting a new MOBO anyway. I didn't think the FPS in games was that much higher.
Reply:I would simply say that then if one card lost data, you wouldnt loose everything, if it was spread across two cards
Reply:Toms Hardware has some excellent info on this. (and on most other things gpu related). Have a look here...





http://www.tomshardware.com/forum/245454...