Alright, I've had this thing for a while but I haven't been using it since I've just got an iMac about a month or two ago.

I've upgraded the RAM to 4GB, and everything is running pretty smoothly. Most of my games consist of a older Valve games like Left 4 Dead, Garry's Mod, Half-Life 1 & 2, and The Elder Scrolls Oblivion.

Well, recently I've been into MW2 and BC2 on my console, and I'm just not liking console versions of these games, so I want to move over to PC gaming.

I recently contacted Sony Support, and they take billions of years to answer 1 simple question, so I'm asking a ton here.

Can I upgrade the graphics card in my Sony VAIO VGN-CR220E?
If so, what should I get? (I don't want to get THE BEST graphics card, I just want something thats good. Can play my games, but not be super-powered and cost a fortune. My budget is $150 USD.

Hypothetically, if I do get a graphics card, is there are certain measurement or size to get? I've got a tiny slot on the side of my computer, about 3 inches long, 1 inch wide. (Or somewhere in that range.) Would I install the card in that slot?

I know this is a lot, but hopefully someone can help me with this. I'm dying for answers, and Sony just doesn't want to answer any of my support emails.

All help is greatly appreciated.