Yes, I must confess that bloody cooler tested my patience....
Ok, truth is, I had never come across that type of fixing before, had we had more time, I could have fitted it, but you had work at 3.30 did you not?
To be honest, I looked at that cooler and in my opinion the stock one would probably do just as good a job.
In the Bios we had 34C. Admittedly not under load but that's good enough for me.
If you really want to change the cooler I'd suggest getting a Zalman, Scythe or Noctua.
The stuff I used to clean all CPU/cooler surfaces and clean off all thermal compound was isopropyl alcohol applied with a clean cloth. Available from most chemists for around a fiver a bottle. You may have to tell them what you want it for though cos alkies try and buy that stuff
Cotton buds are also good, used with alcohol, to clean up some areas.
The stock cooler had a thermal pad on it, which was used. Not ideal, but as I mentioned we didn't have a great deal of time. It will, however, be quite difficult to clean off.
If the Gigabyte motherboard has temperature monitoring software on it's CD, install it and report here with temps. If not, download and use Speedfan or similar.
I don't think temps is your problem but I could be wrong.
How's Vista then? What games are running? Did you set your speakers up ok?
Keep us posted.