Upgrading my graphics card?

[crisosphinx]

The Dell website (assuming http://www.dell.com/us/p/xps-8500/pd) doesn't say what motherboard you have, but it shows a Radeon HD 7870 is possible, so at least you know the case will have room for the GTX 660 card. As for the fans, i think the case already has all the fans it can carry (assuming one in the front and one in the back). You can probably make do with the current airflow it provides, but if you're planning on adding more fans, you're going to need a new case.

Well, mine doesn't have a AMD Radeon HD 7870. It has a AMD Radeon HD 7570. Would that be much of a difference?

Just make sure your powersupply can handle it and that it doesn't conflict with your motherboard. Generally, you won't know this until you actually plug it in or research around the internet. I think your computer can handle it. GTX 660 might be a bit of a jump. Depends on the vram version you get. If you get the 6 gb of vram, version, then your powersupply should be over 800 watts (counting in RAM, processor, motherboard, disc drives, etc.), I'd assume.