Bought the thermaltake9 and...
 

I installed it in my micro ATX case (i believe that is the term, the small one) and it is flush against my power supply (but a fan takes in the air from that) so I turned on my computer XP started loading, I logged in, and as it was booting the computer turned off. I ended up switching back to my old CPU fan and everything is fine.
Do I need a bigger case now since the ThermalTake is a bit larger?
Thanks in advance

I think maybe you didn't have it seated properly. If you can't install it without hitting your PS then you probably need a bigger case. Also, use good arctic silver, don't use those crappy thermal pads.

Thanks, for the time being, if I don't have arctic silver can I use the thermaltake supplied paste?
I'll try it again I suppose.

Yes you can use the supplied paste. Arctic silver has slightly better heat conductivity, but I don't think it's really necessary unless you are putting a significantly heavy load on your CPU for long periods of time.