Upgrading My PC* | EDIT: Building PC - Help with parts.

[Hitman]

Well, RAM is memory that is about 30-40 times faster than your HDD memory, and is used by Vista, applications, games and so on to put in there some files to load them really fast.

Too less ram makes your PC slow, but if you got 4GB and upgrade to 8GB, you wont notice any performance difference unless you use more than 4GB.

For example: my vista home premium 64-bit uses under windows around ~1.2GB ram. With STEAM, MSN, ICQ, Mediaplayer and FireFox (the usual applications a user runs in background), it uses around 1.5GB.

Especially GTA IV needs a lot of Ram. Seeing that Vista uses ~1.3GB of your ram, and you only got 2GB ram, there isnt much left for GTA IV.

I recommend you 4GB of ram. Games are usually 32-bit applications, that means that a game task cant address more than 1,8GB ram. So you are quite comfortable with 4GB ram. 1,5GB for vista, and the rest for your games etc is more than enough.

Ofcourse there are some exceptions, games that run in 64bit mode, but thats just 5-10 games. (Gothic 3, Supreme Commander, Crysis x64) for example.

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Get 4GB ram, thats the perfect amount for Vista. It leaves Vista enough ram to run all applications very fast, and still has more than enough left for games.