One Card or Two?

[oldkid]

I can understand running two video cards if you're running two monitors, but is there any advantage to multiple cards when you only run one monitor? I'm trying to put together a new computer and must decide if I should go with more memory on one card, or less memory on each of two (I can't afford to go more memory AND two cards). I'm not a heavy gamer, I use AutoCAD to do architectural/engineering drawings, but I found that a good gaming machine works pretty well for 3D drawings and it's always nice to impress friends with how good the games look. I'm looking at Dell, and they seem pretty locked in on Nvidia for graphics on their higher end machines, so will probably go that route (with maybe an ATI TV tuner), but I don't want to be stuck with video card(s) that will have to be replaced when I need more graphics power.

[paulix]

nVidia uses SLI technology for multi-gpu processing to essentially double preformance. According to nVidia, cards from two separate retail companies will work together in SLI mode, but they must be the same GPU model (e.g. G70, G73, G80, etc). The cards may have different BIOS revisions, different default clock speeds, or even different memory sizes; however, the fastest card, or the card with more memory, will run at the speed of the slower card or disable its additional memory. If your looking at getting a Dell, I believe they have SLI options for certain models. ATI has similar technology called Crossfire. Both have their pros and respective cons.

[wyz135]

use ATi FireGL, good for Architecture and Engineering use.

[-RK]

Nvidia has the Quadro Series of professional cards as well. My father runs a machine shop, and the shop computers use Quadro FX500s pretty effectively.

As a rule, Gaming cards don't always work well with design, 3d modeling etc. but Professional cards will work well with games. ...the only problem is that they cost more. Sometimes a LOT more.

As for your question, you could use SLI or crossfire to run both cards in tandem and it would increase your GPU power by anywhere from 1.1-1.9x. The problem is that you can't double your video memory that way.

SLi is good if you plan on later upgrading your PC with a second card later for more power after the price drops.

...Dells can be scary on upgrades...

[MrWizard6600]

you'd be lucky to get an additional 80% (http://www.xtremesystems.org/forums/showthread.php?t=166820) on the 2nd card from Crossfire and SLI (ATI's and Nvidia's multi GPU technologies respectively)

That demonstration is geared more towards showcasing Crossfire outperforming SLI (which is a bit of a shocker since SLI has been around for alot longer), but it prooves both points effectively).

[-RK]

When I got my second 7600 I was hoping for a lot more than I got... around 60-70% performance boost at low res (800x600, 1024x768) 30-50% at high res (1280x1024, 1600x1200). That's after the four days I spent trying to figure out that the drivers that came with my first PNY card wouldn't run SLi without serious problems (Oh the agony of the vertical blue bars of light).

I think that the performance hit comes back to the fact that I only have 256mb cards.


I'm not sure how far I'd trust that bench...

it shows 3870 CF getting MORE than 2x performance in a couple of games...

[Mike]

use ATi FireGL, good for Architecture and Engineering use.

nVidia's Quadro has dominated the FireGL's for quite some time. Unless you can find a deal on a FireGL, Quadro is the way to go.