Overclocking

We ran the tests in an open stand that was configured as follows:

• Gigabyte GA-965P-S3 mainboard, rev 1.0, BIOS F2;
• Intel Core 2 Duo E6300 CPU (1.86GHz, Allendale, B2);
• Corsair TWIN2X1024-8000UL memory;
• Chaintech GeForce 7900 GT graphics card;
• Western Digital Raptor WD740GD HDD;
• Tuniq Tower 120 CPU cooler;
• Zalman thermal paste;
• Sunbeamtech Nuuo SUNNU550-EUAP (550W) PSU;
• WinXP SP2 OS.

During CPU overclocking the mainboard worked almost impeccably. In case of over-overclocking we didn’t use Clear CMOS, not a single time: the board would restart on its own. The only inconvenience in my humble opinion, is that the mainboard wouldn’t stop after restarting and offer to reset the wrongly adjusted parameters, it would continue booting the operating system.

Another problem occurred when we tried to adjust the memory timings. When we set CAS Latency 5.0, all utilities would still display CL 3.0. And the problem was only with the way the system displayed the parameter value, because the CL was really set to 5.0, and not 3.0. If it had been that low, the CPU overclocking would have been seriously limited, as at about 1GHz frequency the memory cannot work at CL 3.0, and in our case it worked just fine. With other memory timing settings, as well as for CL 3.0 or 4.0, the value was displayed correctly. At CL 6.0 the mainboard wouldn’t boot.

So, how did the overclocking go? Everything turned out excellent! When we increased the voltage on the chipset North Bridge by 0.2V and the processor Vcore up to 1.45V, the system worked stably at 500MHz FSB! We tested the system for stability with S&M utility and a couple of Prime95 running in parallel.

We couldn’t get beyond that: at 510MHz the mainboard wouldn’t start and the frequency would drop down to the nominal values again. And at 505MHz FSB the OS would boot but the system wouldn’t pass the stability tests. In fact, it doesn’t mean that the mainboard cannot work at over 500MHz FSB frequency, maybe we exhausted the processor overclocking potential. So far the overclocking record for this CPU was set with ASUS P5B Deluxe/ WiFi-AP mainboard and equaled 493MHz FSB.

Well, the preliminary results have been obtained and they are simply excellent. Now we should check out how this mainboard would work with a new BIOS version. It is especially interesting because they promise improved overclocking opportunities with Core 2 Duo E6300 and E6400 CPUs.

We reflashed the BIOS with the new F6 version from Windows with the help of @BIOS utility. It is very simple to work with: you can save the current version of the BIOS, and then reflash the BIOS from any storage device or upload from the manufacturer’s website.

The new version didn’t bring us any new features. The only thing that changed was different arrangement of the parameters in groups and the BIOS became more colorful: there appeared colored and blinking optioned.

For example, the higher memory voltages are now highlighted:

However, now you can increase the FSB frequency to 700MHz instead of 600MHz ?Gigabyte has always been in love with unrealistically high limits.

The issue with incorrectly displayed CL 5.0 setting (that was reported as CL 3.0) has been corrected, however the overclocking features of the mainboard have turned somewhat worse, despite our expectations. Now it stopped starting after 505MHz FSB, worked not very reliably at 500MHz FSB, so that we managed to get it to run stably only at 495MHz FSB.

Well, if it hadn’t been for the strange issue with BIOS reflashing we would have never found out how terrific Gigabyte GA-965P-S3 mainboard could be for overclocking. By the way, when we refalshed the version F2 back, we no longer experienced any issues with the Q-Flash utility. We got our great overclocking options back as well as the issue with incorrectly displayed CAS Latency setting :)