After I exchanged my IS7 for an IC7-G, I now have the following overclocking results (1.4 BIOS):
FSB - 265
I'm pretty sure that my CPU is holding me back from any higher speeds.
CPU - 3.45 GHz
My 2.6C (6/11/03 Costa Rica Retail Box) ran 3.25 at stock voltages, but needed 1.6V to run at 3.45. I also briefly ran at 3.51 (270 FSB), but need 1.65V to run stable. The temps were too high at that speed for my comfort. Also noted that BIOS VCore settings were consistently .02-.03 V higher than what is reported by HW Monitor. Currently, it shows 1.58V.
Temps - 42 C idle 50 C load (20 C ambient, 26 C case)
Abit BIOS tends to give higher temps than other brands. From my H20 setup, my water block is 33 C at load. In my AMD setup, that equaled about 42 C CPU temp. Also interesting is the PWM temp is showing 40 C load on the IC7-G. On my previous IS7, the same PWM temp under similar conditions was 10-12 C higher.
Memory - 5:4 Ratio 212 MHz 2-2-3-6 @ 2.6 V GAT - Auto
The XMS memory has plenty of headroom left as I've run them up to 225 MHz on other systems. Of all the components I've purchased, the XMS memory has impressed me the most.
Testing - Prime95 24 hours and 8 hour loop of 3DMark2001
No failures. I tried 1.575 Vcore, but got failures after a couple hours.
Other Observations
I didn't mess with the NB cooler since I don't know of a better cooler that is designed for the IC7-G. I would usually replace the pink TIM junk with AS3, but decided against that since the 875/865 chips are bare die (like AMD CPUs). Interesting note is that the NB fan on my previous IS7 show 7K RPM and made quite a racket. On the IC7-G, the fan looks the same but runs at 6K RPM and is noticeably more quiet. Since my H20 system is pretty quiet to begin with, this makes a big difference for me.
Final Thoughts
This is the max overclocking for my comfort level. With better H20 cooling, I could probably get to 3.6 GHz, but would need around 1.7 VCore to do it. Since I am at the point of diminishing returns here, I don't think it's worth the extra 150 MHz.
I decided to get the 2.6C instead of 2.4C since my target CPU speed was 3.5 GHz. For the 2.4C, I would need to run a 3:2 memory ratio plus a 285-290 FSB. Since there are only a handful of reports of IC7-G running at > 275 FSB, I didn't want to press my luck.
FSB - 265
I'm pretty sure that my CPU is holding me back from any higher speeds.
CPU - 3.45 GHz
My 2.6C (6/11/03 Costa Rica Retail Box) ran 3.25 at stock voltages, but needed 1.6V to run at 3.45. I also briefly ran at 3.51 (270 FSB), but need 1.65V to run stable. The temps were too high at that speed for my comfort. Also noted that BIOS VCore settings were consistently .02-.03 V higher than what is reported by HW Monitor. Currently, it shows 1.58V.
Temps - 42 C idle 50 C load (20 C ambient, 26 C case)
Abit BIOS tends to give higher temps than other brands. From my H20 setup, my water block is 33 C at load. In my AMD setup, that equaled about 42 C CPU temp. Also interesting is the PWM temp is showing 40 C load on the IC7-G. On my previous IS7, the same PWM temp under similar conditions was 10-12 C higher.
Memory - 5:4 Ratio 212 MHz 2-2-3-6 @ 2.6 V GAT - Auto
The XMS memory has plenty of headroom left as I've run them up to 225 MHz on other systems. Of all the components I've purchased, the XMS memory has impressed me the most.
Testing - Prime95 24 hours and 8 hour loop of 3DMark2001
No failures. I tried 1.575 Vcore, but got failures after a couple hours.
Other Observations
I didn't mess with the NB cooler since I don't know of a better cooler that is designed for the IC7-G. I would usually replace the pink TIM junk with AS3, but decided against that since the 875/865 chips are bare die (like AMD CPUs). Interesting note is that the NB fan on my previous IS7 show 7K RPM and made quite a racket. On the IC7-G, the fan looks the same but runs at 6K RPM and is noticeably more quiet. Since my H20 system is pretty quiet to begin with, this makes a big difference for me.
Final Thoughts
This is the max overclocking for my comfort level. With better H20 cooling, I could probably get to 3.6 GHz, but would need around 1.7 VCore to do it. Since I am at the point of diminishing returns here, I don't think it's worth the extra 150 MHz.
I decided to get the 2.6C instead of 2.4C since my target CPU speed was 3.5 GHz. For the 2.4C, I would need to run a 3:2 memory ratio plus a 285-290 FSB. Since there are only a handful of reports of IC7-G running at > 275 FSB, I didn't want to press my luck.
