Why you can trust Tom's Hardware Our expert reviewers spend hours testing and comparing products and services so you can choose the best for you. Find out more about how we test.
Firmware And Overclocking
The Pro4 uses ASRock's usual UEFI that's immediately familiar to anyone who's recently used the company's boards. Category tabs across the top of the screen group related settings into the same page. It's nearly identical to other recently reviewed ASRock boards, so I'll only provide a quick recap and note a few other features.
The first thing you'll notice is support for FHD resolution in the UEFI. I'm not usually one to complain about the grainy picture when messing with the BIOS, but 1920 x 1080 certainly looks nicer than 1024 x 768 on a modern display. Not only is it a crisper picture, but you can view more settings at once.
Once again you're treated with a My Favorites page. This is becoming almost standard on boards now, and I'm a big fan. Simply hit F5 on any setting and it's copied into a custom page — very handy for gathering your most commonly used settings in a single place. Other typical ASRock features include BIOS update over network, quick select configuration slots, and the ability to import and export BIOS settings to a disk, including hard drives.
Being a Z board, the Pro4 gives the expected controls over CPU multipliers (including core-specific multipliers), BCLK frequency, BCLK ratio straps and cache multiplier. The Pro4 comes with three default overclock settings: 4.5GHz at 1.23V, 4.6GHz at 1.28V, and 4.7GHz at 1.4V VCore. These are also mirrored in A-Tune, ASRock's tuning application within Windows. The last setting seems a little overaggressive, but the other two are perfectly reasonable. Manual voltage control is what you'd expect for CPU, CPU cache and RAM.
BIOS Frequency & Voltage Settings (For Overclocking)
| Base Clock | 90-300 MHz (0.1 MHz) |
|---|---|
| CPU Multiplier | 8x-120x (1x) |
| DRAM Data Rates | 800-4000 (200/266.6 MHz) |
| CPU Vcore | 0.80-2.00V (1 mV) |
| VCCIN | 1.20-2.30V (10 mV) |
| PCH Voltage | 0.80-2.00V (1 mV) |
| DRAM Voltage | 1.165-1.800V (5 mV) |
| CAS Latency | 4-15 Cycles |
| tRCD | 3-20 Cycles |
| tRP | 4-15 Cycles |
| tRAS | 9-63 Cycles |
Despite its low price and 4+2 VRM, the Pro4 can push our Test i7-4790K close to its limit. Knowing our i7 sample isn't the best overclocker, and seeing the limits of a smaller VRM on the last boards I visited, I wasn't sure what to expect. But the VRM heatsink does its job well. Even at the chip's 4.4GHz turbo frequency I saw no throttling or stability problems. Our sample tops out between 4.5GHz and 4.6GHz, so hitting that maximum looked promising. Using a 45 multiplier at 101.1 MHz BCLK yielded a perfectly stable 4.550GHz at 1.274V. I ran into problems when bumping it any higher. For those with locked multiplier CPUs looking for some extra performance, the Pro4's BCLK is fairly flexible. Cold booting at 104MHz is no problem, but pushing it to 104.5 causes instability.
I measured a small RAM voltage cheat on the Pro4 of 0.004V. Not big, but if you're a stickler in controlling your voltage, bumping the BIOS setting down by one tick keeps it honest. RAM timings can be set for primary, secondary and tertiary settings, and XMP profiles are properly recognized. However, the XMP profile bus ratio will not automatically correct itself when changing the BCLK strap. So if you use the 1.25 or 1.67 strap, make sure you slow down the RAM frequency accordingly.
The Pro4 also has decent chops with RAM overclocking. Stock 2800 XMP settings proved no problem with two modules. It remained stable after increasing the BCLK to 103MHz through A-Tune. However the board could neither cold boot nor hold up to heavy stress testing when these same settings were applied in the UEFI. I could run benchmarks without problem, but Prime95 in Blend mode using half of the RAM capacity resulted in rounding errors. Some people may be a little lax in their RAM overclocking, but I demand unquestionable stability. A 101.5MHz BCLK for DDR3-2842 at XMP timings was the best the Pro4 could stably hit with two modules.
Four modules would not boot at 2800. Dropping to DDR3-2666 settings engaged the 4:3 ratio with a 10x multiplier, though I kept the 2800 XMP timings. A BCLK of 104MHz successfully booted, but again I encountered rounding errors in Prime 95. The best I could do was a 100.5MHz BCLK for a max speed of DDR3-2680. That's respectable for four modules, but it could be better.
The application suite is exactly the same as previous ASRock boards we've reviewed. The App Shop is a quick place to download all the utilities and firmware updates for the board. XFast LAN and RAM give you network prioritization control and RAM Disk support, respectively. The Restart to UEFI is a simple app that does exactly what it says on the tin, but it's undeniably useful when meticulously tuning the board. A-Tune provides overclocking and tuning settings and system monitoring info from within Windows. The Tools section of A-Tune also has links to the other utilities.
