michaelleung: You can upgrade Dell computers now?
Sure. Dells are standard enough that it is not difficult. They even use pretty decent power supplies. The days when Dells had too many proprietary parts were quite a few years ago.
The slimlines are harder to work with, because they are very tight. Some of the high-end XPS have proprietary power supplies, but those power supplies have enough capacity that they won't need upgrading. Sometimes you'll run into one that wants ECC RAM. But on the whole, they're not hard to work with.
PaladinHeart: My dad tried it in his computer and it wasn't being detected by his computer either. Guess I got a bad card. Hopefully NewEgg will give me another one.
Newegg will do a same make and model replacement with no restocking fee. Contact customer support to set it up.