Gigabyte GA-EX58-UD5 X58 Motherboard Review

Overclocking Results

Overclocking the i7-920 just got a little more interesting as Maximum PC reported stumbling upon unlocked QPI and memory ratios on i7-920s being shipped to consumers recently. Daily Tech wrote a follow-up article and confirmed these findings with Intel. According to Daily Tech, Intel’s official response was “We made a marketing decision to unlock them for the launched product due to requests from some of our customers.”

Armed with this new information, and Ryan’s previous article on how to overclock i7s, I was confident I could get a stable overclock around or over 4GHz just by using standard air cooling, specifically the Zalman CNPS9900LED heatsink coupled with three 120mm fans and an 230mm exhaust fan in our Thermaltake Element S case.


To start, there are a couple options users have for overclocking with the GA-X58-UD5. For those who don’t want to manually configure memory ratios and BCLK in the BIOS, Gigabyte includes Easy Tune 6 with a graphical user interface that gives three options for “on-the-fly” overclocking. These options will overclock i7-920s to 2.8GHz, 3.0GHz, and 3.2GHz with a push of the button. Or, at least that is how it’s supposed to function. Most of these utilities are pretty buggy and don’t seem to be polished products yet.

We like to have a little more control of our overclocking results here at PCPer, so I manually configured the options I wanted in the motherboard BIOS. After updating the GA-X58-UD5’s BIOS to the current F5 version, I started to on my journey.

After a few hours of tweaking, as well as making a few mistakes because of the uniqueness of the i7 architecture in relation to overclocking, we were able to get a solid overclock of 3.78GHz. The i7-920 has a locked CPU multiplier at 20x, so we steadily increased the BCLK in 5MHz increments until we hit some stability issues then we back off the base clock in 1MHz increments. Since everything is integrated together, our QPI and DRAM frequencies increased dynamically. 

Check out the table and screenshot below for more details:

 

While these results aren’t earth-shattering, I was pretty impressed with how the i7-920 overclocked on air cooling alone. We were actually able to get our highest overclock around 4.2GHz (210×20), but at that speed we were experiencing POST errors during stability testing. So, we backed it down to 3.78GHz and the POST errors disappeared.

We believe using water cooling or other better cooling solutions on the GA-X58-UD5 could help users reach speeds well over 4.2GHz and beyond. It’s really just a matter of balancing the BCLK, CPU multiplier, QPI, and DRAM frequencies and timings to get a stable overclock at idle and load temps you can live with.

One item to note is the CPU multiplier seems to change after setting it at 20x in the BIOS. In the screenshot above, you’ll notice that the multiplier reads 21x in CPU-Z. This is highly unusual because this option is locked in the BIOS and cannot be increased over 20x. It can be decreased below 20x, but not increased past 20x. However, this multiplier figure actually works right with our final speed because 3.78GHz actually equates to 180×21. Maybe this is part of how the i7’s integrated memory controller functions, but it still makes me wonder if Intel has other components of the i7 unlocked and vendors aren’t allowing users to configure these new unlocked items in the BIOS yet. Hopefully we’ll have more information on this at a later date.