First order, get one of these:
Hyper 212 +
My personal favorite for socket 775 if you got room in your case,
There are a few cheaper alternatives as well.
As for overclocking, I will try to give you some idea.
1. Download the BIOS manual if you do not have one already to know what all the settings are.
2. Go to BIOS and save your current stock settings. Most motherboards have an option to load default or optimized settings. If yours do, then you do not need to save. If not, it is wise to save the default settings.
3. Find out all the power saving options in BIOS such as intel speed spectrum, CIE, etc. and disable them.
4. Find the RAM timing and voltage settings in BIOS and switch it to manual. Then go in there and set those to the manufacture settings. An example will be 8-8-8-2T and voltage 2.0V (assuming DDR2). Google your RAM to find the manufacture settings.
5. Go to your RAM multiplier in BIOS and put it at LINKED and SYNCED.
6. Find where you need to increase your FSB (Front Side Bus) and increase it by 50Mhz.
7. Hit F10 to save your settings, and reboot.
8. Run Intel Burn Test for 3 iterations to see if stable.
9. If stable, reboot, go into BIOS and increase FSB by 50 Mhz more. Rinse and repeat.
10. If unstable, bump Vcore by one notch. Reboot. Run IBT for 3 iterations. If still unstable, you may have to play around with HT (or Vtt), SB and NB voltage. But never increase by more than one notch at a time.
I'm not a budget, so would you recommend the Tuniq 120?
If so, should I get the 120 or the 120 Rev1?
Are these the same? http://www.modster-pc.co.nz/shop/adv...er+120&x=4&y=7