I was overclocking my new rig, consisting of an Asus P5K-E Wifi/AP, and an Intel Q6600, and a GeForce 7300 LE (till 7600GT is replaced...). I was steadily increasing the FSB. At 300 Mhz, I obtained these results in Sisoft Sandra and PCMark05.
Then, I upped the FSB to 320Mhz, and it would not boot. I decreased it to 310Mhz, and booted, however it was giving "Rounding errors" in Orthos. First thought it was the CPU voltage, and increased it, but still nothing. The FSB Strap was set at 200Mhz, giving a DRAM Frequency of around 1260Mhz. I then tried decreasing the DRAM Frequency, by increasing the FSB Strap to 266Mhz. It booted, and ran Orthos successfully for 4 hours. I then ran the benchmarks again (Sandra & PCMark05), and the PCMark05 obtained a relatively low mark. Below are the results:
While I considered the decrease in memory bandwidth normal, due to the decreased mem frequency, I cannot understand the 32% result loss in PCMark05, while the Processor tests obtained an average of a 3% increase in performance.
Any one can explain why is there such a loss in the PCMark05 results, when I changed the FSB Strap from 200Mhz to 266Mhz?