I'm going to cut through the chase here and dive right into overclocking. I began with a FSB, SDRAM, and PCI ratio of 133:133:33. No go. System locked up. Upon rebooting, I was taken directly into the BIOS safe mode to recover. Then I tried 133:100:33. Another no go. At this point, I figured luck wasn't going to be on my side. After spending countless hours of tweaking this and tweaking that, I had to settle on the 100:100:33 ratio. Too bad there's not a 100:133:33 ratio.
After going with a 100:100:33 ratio, I started increasing the frequencies in 1MHz increments. The best I could get was 120:120:40 and the processor was running at 840MHz at a core voltage of 1.75. While 840MHz isn't too bad, my overclocking woes are probably being hampered due to the processor itself which was identified by SiSoft Sandra as stepping cA0. Most of the success in overclocking the 700E has been reported with stepping cB0.
Just Kidding Folks...
By not being able to reach a FSB speed of 133MHz, the memory is not running close to it's potential and I am not getting the benefit of the AGP divider (which switches automatically from 2/3 to 1/2 when the board reaches a 133MHz FSB). Ironically, it's close to the same setup as my two year old Abit BH6/P3-550E running at a FSB speed of 124MHz. However there is some consolation in that I'm able to run with a 2-2-2 memory timing which provides better performance than the default timing of 3-2-2.
Running Quake3 using the Fastest graphics setting is a good measure of CPU and memory performance. The following graph illustrates the frame rate while running at various processor speeds using 3-2-2 and 2-2-2 memory timings. The FSB, SDRAM, and PCI frequencies are listed under the processor speed. After the default CPU speed of 700MHz, the AGP bus runs overclocked at two times the PCI frequency (i.e. at 840MHz, the AGP bus is running at 80MHz). Another tidbit is that the AGP transfer mode goes from 4X to 2X when overclocking the CUSL2.
For these tests, I used NVIDIA's GeForce2 Ultra running at default clock speeds. Detonator 3 driver version 6.18 with vsync disabled and Quake 3 version 1.17 with texture compression enabled and sound disabled round out the configuration.
The benefits of overclocking are apparent as performance increased around 20-25 frames per second from 700MHz to 840MHz. However, we can't tell if most of the increased performance is due to the extra processor speed or running the AGP bus overclocked. My guess is that latter accounts for most of the increase in this case.
Memory Timing Comparison
Notice that running at the faster memory timing of 2-2-2 offers a nice boost in performance from 3-2-2. The percentage increase in performance also goes up as the motherboard frequencies increase.
Doh, we have a GeForce Ultra here. We definitely won't be playing Quake3 using the Fastest setting!
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