Overclocking The Low-cost System
Let's recap this system's components before we dig into our overclocking experience.
|System Builder Marathon: Low-Cost PC Component Costs|
|CPU||Intel Core 2 Duo e6750||$212|
|CPU Cooler||Cooler Master HyperTX 2||$27|
|RAM||Wintec Ampo DDR2 PC2-6400 - 2 GB||$81|
|Graphics||GeForce 8800 GTS 320 MB||$280|
|Hard Drive||Seagate Barracuda 320 GB SATAII||$80|
|DVD-RW||Sony NEC Optiarc 7170 SATA||$35|
Here we have a CPU, motherboard, and even budget RAM that has a very overclocker-friendly reputation. Even the 8800 GTS 320mb is a great overclocking candidate. There is a weak link however: the 450 W power supply.
While the Fortron AX-450PN is a great budget power supply that can easily handle the e6750 and 8800 GTS at stock speeds, we were really concerned that it wasn't up to taking these components into the upper echelons of overclocking.
We started our overclocking efforts by seeing how the system would respond to a simple FSB increase from 333 MHz to 400 MHz. Surprisingly, the system booted up smooth as butter, and ran stable as a rock with a clock speed of 3.2 GHz. Already, we were at an over 600 MHz overclock with one simple tweak. Encouraged, we trudged on.
RAM was kept at 1:1 with the FSB. Although we had 800 MHZ DDR2 - which is rated for a 400 MHz operation - we weren't too concerned about taking it higher, as the Wintec AMPO we had proved itself to work at up to about 500 MHZ (1000 MHZ DDR2) in earlier testing by Thomas Soderstrom. We raised the RAM's voltage from 1.8 V to 2.1 V to accommodate the higher clock speeds.
We thought we'd increase the CPU voltage a bit before we went further, so we set it to 1.475 V in the BIOS. The ASUS P5K also has a nifty "CPU Voltage Damper" feature we enabled, which keeps the CPU voltage high under load, when voltage traditionally drops.
We kept increasing the FSB speed to 470 MHz, for a 3750 MHz clock speed - that's more than 1 GHz of overclock. At this point the CPU would hit 60 degrees Celsius in an Orthos stress test, which was about as hot as we wanted to see this processor get. (To be clear, the Cooler Master HyperTX 2 cooler was doing a fine job with excellent idle and load temps, considering the overclock.)