The Z170X-UD3 has the same UEFI as Gigabyte's other 100-series boards. Users are presented with a single firmware interface, called Classic Mode. This old-school aesthetic should appeal to seasoned tweakers who learnt their craft on BIOSes of old. Newbies may miss the novice-friendly Startup Guide interface that we saw on previous generation boards, though.
Rather than rehashing the in-depth coverage of Gigabyte's 100-series UEFI firmware from our Z170X-Gaming 7 review, I'll instead call out some of my gripes. It's not all bad though. After I gripe I'll point out one positive change in the UD3's firmware that I'm very pleased about.
The major shortcoming of the UD3's firmware is the fan speed controls. They leave a lot to be desired.
This board's firmware-based fan speed controls are limited to predefined profiles for silent, normal, and full fan speeds, or a manual option where a PWM duty cycle step can be assigned across the range of CPU temperatures.
These extremely limited fan speed controls are a stark contrast to what's available from some of the competition. At least we get full-featured fan speed controls in Gigabyte's System Information Viewer utility for Windows. The company tells us that it's working on implementing these same controls in the firmware, so we'll keep an eye out for that update in the future.
When testing the Z170X-UD3, I was pleasantly surprised to find that the firmware no longer messed with the CPU's Turbo multipliers when the memory multiplier was changed. You can now safely enable an XMP profile or manually adjust the speed of your RAM without the firmware automagically overclocking the CPU. After seeing more and more motherboard makers apply this sleight-of-hand, it's refreshing to see Gigabyte back away from this practice. Hopefully other motherboard makers follow suit.
Overall, the UD3's firmware is perfectly functional, and it has enough knobs and dials to satisfy all but the most hardcore tweakers. A smorgasbord of multipliers, voltages, timings, and power settings is available for those who want to get tuning.
As with its firmware, the Z170X-UD3's suite of tweaking and monitoring software is carried over from Gigabyte's other 100-series boards almost entirely unchanged. For full coverage of the Windows software, check out our Z170X-Gaming 7 review.
The only difference between the Gaming 7's software and the UD3's is that the Ultra Durable board's interface has a blue theme instead of the industry-standard red that anything with the "gaming" sticker needs to carry. Color choices aside, Gigabyte's Windows software utilities are well laid out, easy to use and fully-featured.
After our lament of the woeful state of the UD3's firmware-based fan speed controls, it's worth spending a few moments on the excellent fan-control functionality the board's Windows software offers.
Despite its name, System Information Viewer is also the place to go to adjust this board's fan speed controls. Here you can configure an ideal fan response curve by adjusting five points on a graph of "fan workload" (or speed) versus CPU temperature. There's even a calibration function that measures the actual speed ranges of the fans connected to the board. This ensures each fan has an accurate profile.
A fixed-RPM mode, as its name suggests, spins the fan at a constant RPM—at least until CPU temperatures reach 70°C, at which time the fans will run at full speed. Gigabyte also bakes in a handful of pre-defined profiles for quiet, standard, performance, and full speed fan operation, which round out the available fan speed control options. All in all, this fan control functionality is superb. I just want to see this level of control in the firmware as well.
Before we get into our overclocking tests, we should note that a given CPU's frequency potential (also known as the silicon lottery) and your choice of CPU cooler tend to have a greater impact on overclocking results than your choice of motherboard does these days. Still, you want the journey to peak clock speeds with modern CPUs to be as fun as possible. The quality of the overclocking experience is where your choice of motherboard becomes important. Ideally, you want a motherboard that will help you along the way, not one that forces you to become too acquainted with your clear-CMOS jumper.
To find out what kind of travel companion Gigabyte's Z170X-UD3 will be on this journey, we put it through its paces using a Core i7-6700K CPU cooled with Cooler Master's Nepton 240M. The Nepton has a 240-mm radiator, and before it was superseded by the company's MasterLiquid Pro 240, it had a $110 asking price. This puts it towards the high end of the range of coolers that might be seen in a system built around the UD3. That said, it should do a good job of keeping our four Skylake cores from getting too torrid as we push the clock speeds up.
The first stop on our overclocking journey is the firmware. Advanced Frequency Settings, under the M.I.T. menu, provides a Performance Upgrade option with presets from 20% to 100% in 20% increments. These options correspond to clock speeds from 4.3GHz to 4.7GHz in 100MHz steps.
With a 20% Performance Upgrade, the firmware supplied our CPU with 1.25V. All Turbo multipliers were set to 43x and the base clock remained at 100MHz. This collection of settings was completely stable in our Prime95 stress test. We saw no signs of any throttling and temperatures maxed out at 78°C.
Our quest for more speed brought us back to the Performance Upgrade firmware option, this time for a 40% upgrade. Rebooting into Windows, we found that the firmware was still supplying 1.25V to the processor, while Turbo multipliers were set to 44x. Our Prime95 torture test was completely stable at 4.4GHz, and the Nepton was keeping temperatures in check with a maximum of 79°C.
We repeated this same process with the 60% Performance Upgrade options and we were rewarded with a stable 4.5GHz clock speed with a core voltage of 1.25V. Prime95 was stable with no thermal throttling, but temperatures rose to 80°C during the run.
With the 80% Performance Upgrade option locked in, we booted to the Windows desktop at 4.6GHz with a core voltage still at 1.25V. This wasn't enough voltage for a stable Prime95 run, however. Worker threads instantly saw errors once the test was kicked off.
Despite our previous failure, we decided to shoot for the moon and try out the 100% Performance Upgrade option. In an attempt to secure a stable 4.7GHz clock speed, the firmware supplied our chip with 1.380V. Our Prime95 stress test was not impressed, instantly spitting out errors. A perfect 100% was out of reach.
In our attempt to leave no overclocking stone unturned, we moved on to the firmware's CPU Upgrade option. This second automatic overclocking method has settings for the Core i5-6600K and Core i7-6700K. The first two pre-baked profiles for the Core i7-6700K, 4.4GHz and 4.5GHz, used Turbo multipliers of 44x and 45x, respectively. Both fed the CPU the same 1.25V to the core, and both were completely stable in our Prime95 run. The 4.6GHz preset didn't fare so well. With Turbo multipliers set to 46x and a slightly elevated core voltage of 1.26V Prime95 still gave errors almost immediately on startup.
With the firmware's automatic overclocking options thoroughly tested, we turned our sights towards Gigabyte's Easy Tune application. Easy Tune pairs a pre-baked overclocking profile with an auto-tuning feature that increases clock speeds bit by bit, testing stability along the way.
Enabling Easy Tune's OC profile instantly gave us a 4.4GHz clock speed at 1.25V. This config was completely stable in our Prime95 stress test. It also yielded the same configuration as the 4.4GHz CPU Upgrade firmware option.
Next, we tried Easy Tune's auto-tuning feature. Once we clicked through the obligatory warning screen, up popped a 30-second countdown timer with a message alerting us that a system reboot was required to kick off the auto-tuning process. Once Windows came back up, Easy Tune kicked things off at 4.4GHz and steadily increased clock speeds in 100MHz increments, running stress tests at each point along the way. The utility made it all the way to 4.6GHz before declaring victory.
The board achieved this result with 46x Turbo multipliers and a core voltage of 1.28V. Testing with Prime95 showed the system to be perfectly stable with no throttling, and CPU temperatures peaked at 84°C. The whole auto-tuning process lasted a little less than ten minutes.
Having thoroughly exhausted the board's automatic overclocking features, it was time to step out on our own with manual tuning in the firmware. We started by tweaking the multiplier alone, with all the voltages left at "auto." This got us to 4.5GHz using a 45x multiplier alongside the standard 100MHz base clock. At this speed, the firmware was supplying our CPU with 1.25V. This config proved to be stable during the Prime95 run. We saw no signs of throttling and temperatures topped out at 81°C.
Seeking more speed, we took voltage control into our own hands. By manually setting the core voltage, we made it to 4.6GHz at 1.29V. Prime95 was completely stable with no throttling, and our Nepton was keeping temperatures in check at or below 86°C.
Unfortunately, pushing higher than 4.6GHz proved fruitless. Either Prime95 would find errors on one or more worker threads, or we'd push voltage so high that we'd hit thermal throttling.
A 4.6GHz final clock speed is very respectable for this CPU and cooler combination. It is, in fact, only 100MHz lower than the highest speed we've ever achieved on any Z170 board, so those numbers are right where we'd expect to be for our multiplier overclocking results.
The fun doesn't end there, though. Skylake K-series CPUs allow tweaking of the base clock without having to run other system devices out of spec. That's thanks to a revised reference clock architecture that decouples the PCIe and DMI bus speeds from the base clock. While it's much easier to overclock using multipliers alone, we ran a quick test to see how the UD3 fared when overclocking with base clock tuning.
We first tried for a 200MHz base clock, leaving everything else on "auto." We quickly ended up with a board that didn't POST. Thinking our folly was in leaving the other settings on auto, we manually set the CPU Multiplier to 20x and the DDR4 speed to 3000 MT/s. Those settings didn't help matters, unfortunately, so it was time for another trip back to the clear-CMOS jumper. We decided to try a different tack at this point.
Starting with the stock base clock of 100MHz, we increased its speed in 10MHz increments, testing stability along the way. We didn't make it very far, however. At 130MHz things started to unravel for the UD3. After briefly seeing the firmware splash screen the system rebooted and we landed back in the boot failure guard. 120MHz was perfectly stable, however. Ignore the insanely low core voltage reading by CPU-Z below. CPU-Z was having some trouble with this board, it seems.
In the end, 120MHz was as far as we could push base clocks with this board. With the availability of K-series unlocked chips and base clock increases being more a novelty than a staple for today's overclockers, this low result isn't really anything to worry about.
Overall, overclocking on the Z170X-UD3 was a pleasant ride. The pre-baked profiles in the firmware worked fairly well, leaving only 100MHz of clock speed on the table. This last morsel of speed was easily achieved using both manual tuning through the firmware, as well as Easy Tune's auto tuning feature. While I would have liked to have control over the stress tests that the auto-tuner uses, it's hard to fault the outcome.
Now that our overclocking journey has come to an end, let's see how the UD3's performance stacks up.