I recently upgraded from an Athlon XP 3200+ overclocked to 2.6GHZ. It was a simple case of upping the FSB, changing the Multiplier and upping some voltages and sticking a great big fan and heatsink on the cpu. All very simple stuff with the single core chip.
Now I have upgraded to multi core and it involves dozens of new settings and a corrupted windows installation so am having to reinstall windows AGAIN!
Will be on and off on the laptop while im sorting it out but it does mean I dont have access to any of my emails or personal folders until its sorted. Oh the joy's of modern computing



