I thought I just need to buy 8800GTS and insert and use. But i have to look after the temperature as well? Umm, could someone explain? Thanks.
If you are a gamer or use graphic intensive programs, it will use the video card GPU, and it can heat up. You need a good fan to cool it. The video card that you want to buy is a high end card, and should be fine for you, although you may explain why you need to buy it. It does have a good fan. The answers you get here will vary on the reason for the need.
I am building a new PC soon. My PC is very dated and can't even load simple programs well. P4 @ 1.8 GHz 256mb RAM Geforce 440 MX w/ 32mb 20GB HD and upgrading to: E6600 8800GTS w/ 320 mb 2GB RAM 300GB HD because I want to work faster, and also play games like Crysis. Thanks.
GPUs cool themselves, albeit noisily, you just have to make sure your case has a reasonable fan in it, and that's about it. You should only be concerned if one of the fans gets stopped for any reason (so make sure it doesn't happen! )