Multiple Video Cards

I'm currently browsing parts for a new computer, looking to spend somewhere between $800-$1000, and most of my parts actually line up with the suggested machine for the $1000 level box in the sticky. Something that puzzles me is the advantages/disadvantages of choosing two video cards over having a single one with the same total megabytes/gigs.

I understand there are more variables than the 512 or 1 gig stat, but for otherwise identical cards is price the only deciding factor?

Thank you.

cant really get too technical
but it jus handles the video data more efficiently accross 2 cards
rather than a single card being stressed

and u cant really jus look at teh mb either

a 512mb "performance" model will run much better than a 512mb "budget" model

Two cards in SLi/Crossfire will outperform 1 by a substantial margin provided they are the same type and the only difference is the amount of video RAM.

Essentially, Crossfire/SLi work like this.

One card renders half of the screen, the other renders the other half. Or, in some modes, one card renders one frame, and the other cards render the next frame, etc etc. There are two other forms of rendering, but they are least common: Split frame, alternate frame A, and alternate frame B, and then true mode (aka half the screen as explained above)

Thank you very much for the replies. Now when I get just a little more money it'll be time to go shopping

If your new at this i reccondmend a 1 graphic based system to avoid any compatabilty or driver issues.

CPU: E8400: runs at 3ghz, well priced, dual core with 45nm technology which would mean high effeciancy. Also 6mb of cache.

Motherboard: Anything 1333fsb/45nm compatablie, mATX or ATX sized. mATX is a cut down version of ATX. Also there are very few mATX motherboard with SLI or Crossfire support (SLI = Nvidia based multiple card support, Crossfire = ATI based multiple card support). You cannot run 2 ATI cards on a SLI based motherboard, but you can run a single card on it. Also mATX will have a maximum of 4 expansion slots where as ATX can have up to 7 slots. (PCI, PCI express, PCI express x16 which is your graphic card slot). Basically straight to it, if you want more upgradabilty go ATX, if you want a more compact system with a smaller case go mATX. There are so many I could advise that I cant narrow it down.

Memory: 2x2GB 800mhz Ram as thier cheap as chips now days. 1066 ram is also a decent option but you will hardly see the difference.

Graphic Card:ATI HD4870 or Nvidia GTX260 both have good price/performance.

Case: ATX if you have a ATX sized motherboard, otherwise mATX if you get a mATX sized motherboard (mATX = Micro ATX). with dust filters if possible. And also try to get one with a 120mm exhaust fan space. I advise the ANTEC 300 for either. Its cheap and has excellent cooling.

Power Supply: Corsair VX550 or Corsair TX750. Very well built. THe TX750 will gve you more head room for the future.

Optical drives Your Choice but try to get a SATA based one as the cables inside will be far less messy.


Heres a build I would advise in your price range.

E8400 CPU
http://www.newegg.com/Product/Produc...82E16819115037

Gigabyte EP35-DS3L ATX Motherboard
http://www.newegg.com/Product/Produc...82E16813128337

Adata 2x2GB 800MHZ Memory
http://www.newegg.com/Product/Produc...82E16813128337

Dimond ATI HD4870 Graphic Card
http://www.newegg.com/Product/Produc...82E16814103061

Antec 300 ATX Case
http://www.newegg.com/Product/Produc...pk=Antec%20300

Corsair TX750 Power Supply
http://www.newegg.com/Product/Produc...82E16817139006

Thats just under $800 and I'm sure you can look around for better deals other than on newegg.

Yes im in a boring evening class.

The only problem with multiple GPU's is games that didnt implement support for SLI or Crossfire.

This is purely a sign of Lazy developers who refuse to optimise their games for best performance, and if it happens in the latest DX10 games (LOL - AoC), the game is likely not worth buying because it will still run like crap at high resolutions on any hardware.

But 80%+ of modern games will utilise multiple GPU scaling, and when they do, a pair of ATI 4850's completely obliterates the powerful GTX 280 while costing a significant amount less.

Game developers that dont implement SLI or Crossfire support these days need sacking from the games industry.

You can force alternate frame rendering on a game that doesn't support SLi though, thus getting around it (albeit, at a performance hit compared to full SLi/Crossfire scaling)

Also, a pair of 4850's in Crossfire can't touch a GTX280 except in highly ATi favored games, and even then, said games dislike nVidia in general. A GTX 280 is the best single core solution on the market. The 4870X2 is the best dual core solution (albeit it actually being 2 cards on one PCB)

The best deal in reality is a pair of GTX260s in SLi. It gives the highest level of performance in the highest number of games, followed very closely by a Crossfire pair of 4870s.

I might be wrong about this. I think I am.

Taken from the above link:

The above slide, courtesy of INPAI.COM.CN, puts into perspective the worthy price to performance ratio that AMD is touting, with its upcoming SKU.



I bolded the key words to point this out. There is a massive difference in top end performance compared to price to performance ratio. The very top end is never cheap. This is true for any computer component in almost all cases.

I would personally would wait a few months as the DX11 cards will be out next year, this will aid in a bit of "future proofing". At least this is the rumors floating around.

I personally think the time for upgrading/building a new system is around the spring time 2009. At this time the new cpu chips will be out as well as the new motherboards, suspect that the dx11 cards will be or very near at that point. Even if you do not plan on a complete rebuild it will force the "older" technology down in price. This is my suggestion and will save you money. I can only ever afford to get near the bleeding edge, not on it.

I'll sign that since it's my plan. It will give me the chance to let other people play around with Nehalem so I will know if it's worth it for my needs, or if I should just get a current highend quadcore at a cheaper price. The only other thing that might make me wait a bit longer would be Windows 7.

Price cuts...put off those upgrades for next year...when have i heard that before? =P last year? Computer parts are not like wines - they don't get better with age. The worlds best system at any given point in time is only the worlds best system until the next new thing comes out.

On topic: I really don't think buying 2 video cards nowadays is worth it. Something like an 8800 Ultra (killer price btw, picked one up a few months back) can run any game out there in max settings...no problem. Any more video processing power is just icing. To summarize...I would definitely not hesitate to get a system which you could upgrade with another video card if you want in the future - but realistically - SLI or Crossfire nowadays are overkill. Surely others will disagree, but thats my opinion.


my setup

e8400 stock 3ghz
Gigabyte-DS3L (f8f)
2x2GB Mushkin
8800 Ultra
OCZ GameXStream 700W PSU

My problem is that my computer seems to be on its last legs, and I'll need a replacement ASAP. Ideally I'll have enough money in a month, but I'm hoping to purchase everything and get assembled as soon as I have funds.

Thank you VERY MUCH for all of the great help and suggestions