The very first thing that I wanted to try with the STRIX X99 Gaming is the ability to use the 125 BCLK strap to allow me to utilise my 3000 MHz RAM from Corsair. It was entirely painless, unlike a few other motherboards that I have tried in the past. It reset itself once to initialise the strap, and from there on, it was plain sailing. The system ran flawlessly, and I could not have been more pleased with the ease of use.
One thing that I found a little quirky was the fact that you have the options to set manual voltages, but some of them are still assisted in terms of you not being able to enter a number, and then you have full manual which gives you full control as you’d expect. I’m not sure of the reasoning behind the two, but it did make me scratch my head when I couldn’t figure out why I was unable to adjust the System Agent (SA) voltages by typing in a number that I wanted. Once I noticed that I felt like a right noob. However, you live and learn, and I haven’t seen that before on any previous motherboards.
When it came to overclocking the CPU, nothing phased it. If you pushed the core or cache speed too far, it would simply refuse to turn on, reload stock settings and proceed to tell you that you’ve goofed it. You then have the option to enter the UEFI once more to try again. I tried desperately to get the STRIX X99 Gaming stuck in a boot loop just to see how it would recover, but I couldn’t manage it. The motherboard just reset itself and went on about its business as if nothing had happened at all. I know you shouldn’t typically try to force a motherboard to fail to POST, but it’s just something that I like to cover to see how the system handles it. I was unsuccessful. Darn you, modern technology!
Our CPU sample topped out at 4.2 GHz, just like in our MSI X99 Gaming Pro Carbon sample that we tested. It’s more than likely a thermal and voltage issue for this particular chip. It does not set the standard for 6950X CPUs in terms of its overclocking ability, we just happened to luck out (again!) on the draw. As all of our tests are done at 4.0 GHz on the core and 3.5 GHz on the cache, I did not proceed to take any readings other than to say that the scaling remained more or less linear, and therefore you can expect similar performance when compared to other motherboards on the market (that we’ve tested as well) at this moment in time.
Broadwell-E features something that allows the CPU to overclock each core individually and it allows you to get the best possible performance from each core, rather than being limited to the slowest core. The other benefit to this is that you can now tell the CPU to slow down during heavy AVX workloads. The annoyance with this is that there is no ‘do not drop my speed’ option. There’s auto, and then it drops by one denominator. So, for example you can run at 40x for normal operation, and under AVX you can instruct it to drop to 38x to maintain stability and to keep the heat down. Perhaps this will be changed in future UEFI releases, but I saw no noticeable difference in performance going from another motherboard where you have the option to choose 0 instead of auto or 1.
As far as the memory claims from ASUS go, I did not have any issues at all getting my RAM to boot at 3200 MHz, which is slightly above their rated specifications, and it proceeded to do pretty much everything all by itself. Some of the voltages, such as the SA (System Agent) line, for example, were a little higher than perhaps I would have deemed necessary. However, given that it worked flawlessly, and didn’t even throw a wobbly once, I cannot fault the way that it was set up by the UEFI. I did not try to push the RAM any further as it would require yet more SA voltage and the CPU isn’t mine to break. The sweet spot for RAM on X99 is typically around 3000 to 3200 MHz, any more just requires too much voltage or simply is not stable due to memory controller constraints. While these frequencies were attainable, the voltage may not deem it feasible for 24/7 operation (in my opinion.)