We performed all our tests on a testbed built with the following components:
- Mainboard: Intel DZ77BH-55K (LGA1155, Intel Z77 Express, BIOS version 0083);
- CPU: Intel Core i5-3570K CPU (3.6-3.8 GHz, 4 cores, Ivy Bridge rev.E1, 22nm, 77 W, 1.05 V, LGA 1155);
- Memory: 2 x 4 GB DDR3 SDRAM Corsair Vengeance CMZ16GX3M4X1866C9R (1866 MHz, 9-10-9-27 timings, 1.5 V voltage);
- Graphics card: Gigabyte GV-T797OC-3GD (AMD Radeon HD 7970, Tahiti, 28 nm, 1000/5500 MHz, 384-bit GDDR5 3072 MB);
- Hard drive: Crucial m4 SSD (CT256M4SSD2, 256 GB, SATA 6 Gbps);
- CPU cooler: Scythe Mugen 3 Revision B (SCMG-3100) CPU cooler;
- ARCTIC MX-2 thermal interface;
- Power supply unit: CoolerMaster RealPower M850 PSU (RS-850-ESBA);
- Open testbed built using Antec Skeleton system case.
We used Microsoft Windows 7 Ultimate SP1 64 bit (Microsoft Windows, Version 6.1, Build 7601: Service Pack 1) operating system, Intel Chipset Software Installation Utility version 22.214.171.1240, AMD Catalyst graphics card driver version 12.4.
Operational and Overclocking Specifics
There were no problems during the testbed assembly on Intel DZ77BH-55K mainboard. The board worked impeccably in default mode. When you power on the system you see the following start-up logo:
Unlike other mainboards, the ones from Intel let you select the list of hot keys to be displayed during startup. However, disabling startup image doesn’t produce any immediate benefits, because there I no useful info about the startup progress or system parameters displayed beneath it anyway.
Unfortunately, we had to deal with some difficulties during our overclocking experiments, because the board came with the BIOS version 0074, which was seriously flawed. One of the issues Intel boards have these days is unacceptably large increment for adjusting the processor core voltage, which equals 20 mV. However, in the BIOS version 0074 it was the only increment available. Without raising the Vcore it remained too low for successful overclocking and we got BSOD even before getting to the testing part or the board wouldn’t load the OS at all. And if we raised the voltage by 40 mV, then it would plummet to 1.25 V under heavy load, which was way too high and the CPU got immediately overheated. It looked like this particular BIOS version had Vdroop set to its maximum at all times no matter what you selected for this parameter in the settings. As a result, raising the Vcore by 20 mV remained the only option that would allow us to somehow investigate the board’s overclocking potential. It wasn’t good, but there was yet another obstacle: the BIOS reflashing tool for Intel mainboards didn’t allow us to save the current BIOS version before reflashing it with a new one.
In fact, Intel mainboards offer several ways of updating the BIOS. You can use the Iflash utility in DOS or Intel Integrator Toolkit. The most convenient method recommended for Microsoft Windows users is to download a self-extracting archive, which will automatically reflash the BIOS. However, we used a built-in updating tool, which can be launched by pressing F7 during system startup.
Note that besides the USB drive with the new BIOS update, the list also contains both partitions of the connected SSD, i.e. it supports NTFS file system, unlike many other integrated utilities that come with competitor mainboards.
Once you found the file containing the new BIOS version, you just need to confirm your decision to update.
Everything is very simple, but there is no way to save the current BIOS version before updating it. We rarely need this function, but this was one of those times when we wished we had had it. We could download the 0070 BIOS version from the company web-site dated April of 2012, but there was no guarantee that it wouldn’t turn out even more flawed than the original version 0074. Intel mainboards do not have two BIOS chips that could allow us to test drive the new BIOS version safely, and there is no way of saving the current BIOS version, so we had to take precautions and make sure we had all the benchmarks done for the version 0074 before we reflashed the version 0070. Luckily, we didn’t have to roll back to the older BIOS, because new version 0083 came out. We have already discussed it in one of the previous chapters of this review and we used this particular BIOS version for all our Intel DZ77BH-55K performance and overclocking tests.
The new BIOS version 0083 still has the same issues typical of Intel mainboards, namely there is no way to change selected memory sub-system settings and the processor Vcore may only be increased with a very high 20 mV increment. Some of the shortcomings pointed out in our Intel DZ77RE-75K and Intel DZ77GA-70K mainboards review are also there. When we reset to default settings after overclocking, the CPU Vcore still gets raised by 20 mV for some reason. In Visual BIOS mode memory frequency and Processor Power Efficiency Policy parameter cannot be saved in the settings profiles, and in Classic Mode the profiles do not save the temperature settings of the “Fan Control & Real-Time Monitoring” sub- section. There could be some other issues, too, but we didn’t come across them this time. However, Intel DZ77BH-55K didn’t try to raise the graphics core voltage on its own, like the Extreme series mainboards did. The processor core voltage increased normally, unlike what we saw with BIOS version 0074, therefore, we successfully overclocked it to the maximum frequency of 4.6 GHz at the same time increasing the memory frequency to 1867 MHz.
Since Intel mainboards do not allow us to manually correct some of the memory timings in Automatic mode, we had to stick to 9-10-9-27-2T, while on other tested mainboards we were working with 9-10-9-27-1T. Moreover, we uncovered a very strange issue that we saw in all BIOS versions: the board didn’t let us increase the memory frequency. If we loaded the settings profiles with higher memory frequency or just tried to raise it ourselves, the board would beep twice upon start-up and offer to correct the “faulty” settings.
It took us a while to figure out how we could make this board work at higher memory frequency, but the solution was very simple: just ignore its response. Once the start-up has been paused and you access the BIOS, the memory frequency does not get reset. All you need to do at this point is exit the BIOS without changing anything. Second boot-up attempt should be a success and after that the board will reboot and start up without any problems and maintain increased memory frequency. Everything will go on great until you decide to return to the default settings and then increase the memory frequency again. But in this case you will already know what to do.
Now I just have to remind you that we always overclock mainboards in such a way that they could be used permanently in this mode. Therefore we do not try to make our life easier by disabling any of the mainboard’s features, e.g. onboard controllers, and try to keep the CPU’s power-saving technologies up and running. This time we did exactly the same thing. All Intel power-saving technologies remained enabled and automatically lowered the processor Vcore as well as clock frequency multiplier in idle mode.