hi

my first post?

umm.. boleh kata saya noob la.. I have NULL experience in building my own PC. only what i dream to do. I have followed tech news since 13yrs old(now 16+). I've seen alot. Read alot. Currently, if i wanna build a budget PC, I know

i wish for 8200. but intel 2140 is nice. ;
I wish for a HD3870. But HD3850 good enough la. Would HD3650 be best performance/price ratio? then i want that ;
for PSU, i have no target. I have no idea;

Look at my current home PC:

OS: Windows XP Pro SP2
Proc: Pentium D 925 3.0
Ram: kingston 1024MB
PSU: dunno what brand. 450W
Graphics: HIS X1050 512MB

and some other things i know:
A4 Tech Super Slim Keyboard
A4Tech mouse
BenQ T705 monitor
defect Tsunami Shadow Series XX-117AA Twin Speakers with Subwoofer

Ok, now for my question. Please just recommend a PSU for my dream great budget PC. Do i need 500W for 3850?