After 5 days of trial and improvement, I finally managed to get my system sable after doing quite a lot of overclocking!
Here's what I managed to squeeze out of my machine
AMD Athlon FX60 originally running at 2.6GHz, OVERCLOCKED to max stable 3.01GHz
CPU Voltage changed from 1.35v to 1.50v
Temps: idle 30-35c load 50-55c
GeForce 8800GTS 512 (G92) originally running at 650/970/1650mhz
Overclocked and 100% stable to: 800/1000/1930mhz!
Temps: idle 45-48c load 60-65c
3GB Kingston originally at 200mhz
Overclocked and stable to 220mhz
Added 0.1 of extra voltage
HT bus overclocked to 1053mhz
I've notice a huge improvement!