Desktop Graphics Card Questions

Hi. I have a few short questions about desktop graphics cards, since I have only ever really used laptops. I was considering building myself a desktop at some point in the future.

So firstly, can you put desktop graphics cards in to crossfire/sli yourself? So if I bought a graphics card, then could I buy another of the same card later + combine them? Or do they have to be bought together?

And, secondly, are all graphics cards compatible with all motherboards/processors? (assuming they can be connected correctly)

Also, what would be the minimum you would have to spend to get a graphics card which would run all current games (including metro/crysis) at 40+ fps? £200? And what would be the minimum I would have to spend to build a desktop with the same requirements? around 600?

Thanks

 

Almost all laptops (including the one in your sig) cannot have their graphics card upgraded (despite being "discrete" GPUs, they are soldered to the motherboard in the vast majority of laptops), and somewhere around 2-3 current laptops support dual graphics cards, all of them costing well over $2000. No current single laptop GPU can max out Crysis 1 or Metro 2033 (DX11) at 40FPS. You'd have to buy one of those dual GPU laptops for that. I think you should stick to desktops for gaming.

 

I was talking about desktops actually. I'll make it more clear.

And my current laptop can get about 20/25 fps in metro 2033 in max settings

 

As this is a notebook forum, this would be best served in our sister site, desktop review.

Desktop Reviews - PC Reviews and Desktop Computer Buying Guide