Overclocking
| BIOS Frequency and Voltage settings (for overclocking) | |||||
|---|---|---|---|---|---|
| ASRock Z68 Pro3 | Biostar TZ68A+ | Gigabyte Z68XP-UD3 | Intel DZ68DB | MSI Z68A-GD55 | |
| CPU Base Clock | 95-110 MHz (0.1 MHz) | 100-300 MHz (1 MHz) | 80-200 MHz (0.1 MHz) | 100-300 MHz (1 MHz) | 38-282 MHz (0.1 MHz) |
| CPU Multiplier | Up to 60x | Up to 100x | Up to 59x | Up to 255x | Up to 60x |
| DRAM Data Rates | 1066-2133 (266.6 MHz) | 1066-2133 (266.6 MHz) | 800-2400 (266.6 MHz) | 1066-2133 (266.6 MHz) | 800-2133 (266.6 MHz) |
| CPU Vcore | 0.723-1.52 V (5 mV) | 1.00-1.79 V (10 mV) | 0.75-1.70 V (5 mV) | 1.00-1.35 V (12.5 mV) | 0.80-1.80 V (5 mV) |
| VTT Voltage | 0.77-1.63 V (9 mV) | 1.05-1.70 V (12.5 mV) | 0.86-1.53 V (5 mV) | Not Adjustable | 0.95-1.55 V (20 mV) |
| PCH Voltage | 0.78-1.65 V (9 mV) | 1.05-1.20 V (50 mV) | Not Adjustable | Not Adjustable | 0.78-1.72 V (5 mV) |
| DRAM Voltage | 1.20-1.80 V (14 mV) | 1.30-2.20 V (12.5 mV) | 0.89-2.14 V (5 mV) | 1.20-1.80 V (50 mV) | 1.11-2.46 V (7.25 mV) |
| CAS Latency | 5-15 Cycles | 3-15 Cycles | 5-15 Cycles | 5-12 Cycles | 5-15 Cycles |
| tRCD | 4-15 Cycles | 3-15 Cycles | 1-15 Cycles | 5-16 Cycles | 4-15 Cycles |
| tRP | 4-15 Cycles | 3-15 Cycles | 1-15 Cycles | 5-16 Cycles | 4-15 Cycles |
| tRAS | 10-40 Cycles | 9-63 Cycles | 1-40 Cycles | 15-75 Cycles | 10-40 Cycles |
All of today’s motherboards offer a wide enough range of voltage and frequency settings to satisfy the majority of semi-serious overclockers, yet no motherboard in this price comes with a voltage regulator we'd feel comfortable taking into an overclocking competition. Differences in trace layout also affect signal strength between devices, setting us up for an interesting overclocking comparison.
The chart does not tell the whole story in today’s CPU overclocking chart. Intel actually had the highest stable CPU clock, but it eventually throttled back down to its stock 3.4 GHz frequency after a few minutes of load. This unfortunately took the board with the best CPU stability out of the running in the overclocking comparison. We tried lower voltage, but all that did was delay the onset of the same symptoms. This test was done with maximum power and thermal limits set in the BIOS, of course.
Thus, with the same low price as Intel, Biostar’s reduced-feature overclocking motherboard wins.
Biostar also has the highest base clock, though this is primarily a restriction of our CPU. We have no idea why the DZ68DB could push our processor’s normal 107 MHz limit, but more conservative settings are better for preserving hardware, and when it comes to longevity in a daily use machine, we err on the side of long-term health.
MSI tops our memory overclocking chart with a superb data rate. Biostar sits at the bottom because it wasn’t completely stable at 2129 MT/s and didn’t support BCLK underclocking to assess its capabilities at the same high multiplier.