What to do?

Here are my options.

I want to upgrade my graphics card but heres my options performance wise.

Currently these are my specs


I ONLY GAME AT 1440X900(max my monitor does) i will be upgrading to a 1920 monitor within a year tho!
470W PC power cooling PSU
C2D E8400 @ stock, still stock intel hsf
GA EP45 UD3R mobo
4GB RAM 800MHZ
250gb hard drive
vista 64bit
HD 3850 256MB


i want to upgrade to a HD 4870 or 4890 or gtx 260

to do this i need to upgrade my PSU aswell so im thinking the 610W pc power? or the 750w

Basically this is what i want to do

overclock cpu to 3.2ghz stock
Buy a HD4890
Buy a 610 or 750 w psu from pc power(or corsair but i dont like the fan on the bottom of psus) and im good?

but as you see my cpu is Stock settings so 3.0ghz is that enough for 1440x900 gaming? will i bottleneck the cards?
so the other thing i can do is this

Buy a hd4870 or gtx 260
buy a vendetta 92mm
buy the power supply
and overclock to 3.6ghz


what should i do? btw ive only overclocked to 3.2ghz with stock cooler i hear you can do 3.6ghz with stock but meh..i dont want temps above 60c