I've ASUS Radeon 9200SE and the performance is not so fast but it have quite of much function that it supports, so i plan to overclock it.
I am using stock cooling and didnt plan to change the fan or heatsink. So are there any way to overclock it without using any special heatsink?
I heard that they can flash the bios of the GPU to unlock the core clock.
Any idea?

MSI KT3 Ultra 2MS-6380E
Athlon XP 1800+
12x133MHz
DDR512 PC2700 2-2-2-6
Asus ATi Radeon 9200SE 128MB
Windows XP SP2

The 9200SE is a low end 64-bit card that doesn't support DX9. If you overclock it, you'll have a slightly faster low end 64-bit card that doesn't support DX9...lol! If you're any type of gamer, you'd be better off upgrading. If you insist of playing around with what you have, download ATiTool.

I suggest the Radeon 9600XT 128MB card.

http://graphics.tomshardware.com/graphic/20041110/buyers_guide-14.html

ASUS A7N8X-X
Athlon XP 1800+
8.5 x 200MHz
1024MB PC3200 2.5-3-3-7
Asus A9550GE/TD 128MB
WinME/WinXP Pro SP1