Now,
i'm new to this program, i've just replied once and that was in the games section with quake 3.
if you've been there, you'll know that i'm a computer and a games freak. If ya wanna know something or are just have trouble and need help with anything got to do with computers, hardware, software, games and game consoles, you've come to the right guy.

Now when you put 2 graphics cards in your motherboard, you only get to use 1. It is impossible to use 2. When you install the software and the drivers for the cards, you must pick which one to use.

It is not totally impossible to use two graphics cards! if you want to use two, you have to buy a special graphics card that can be used for SLI.
And to use SLI, you need a motherboard that supports it.
SLI means using two graphics cards at once.
and also, you need to have the exact same type and model of graphics card if you want to use it.

SLI is really useful, but would cost too much.
First you have to buy an SLI motherboard and then two of the same types of graphics cards.

Don't go through the hassle and just buy a good single graphics card like a radeon x800 xt or a ge-force 6800 Ultra.

As you probably already know SLI technology does not give you 100% of performance from both graphics cards, it simply splits some of the magor operations between those two cards. But overall i can tell you after my own experience of testing couple of SLI and crossfire systems that it DOES make sense to spent those money for 2 graphics cards, because it is pretty much 1.5 X faster.

Replying to bozo

In 2005 maybe but this needs updating now because x2 ge force 8800s with 1gb of onboard ram cross fired is UNREAL! thats 2 gig of ram just for the grpahics and then you have all your other ram as well making for seamless game play right now cross fireing is the best thing you could do graphics wise as the best card atm is the 9800 but at 300 pound each its the same price as 2 8800s yeah its a slightly slower gpu and slower ram but you have more of it to more than make up for that

-reply by Barry

Using 2 Graphic cards is NOT increasing your performance really well. It's just better using 1 high end card like you've said.