Z77X-UD4 CPU VRM
We’ll start our Motherboard Tour with a look at the most important part of any motherboard – the CPU voltage regulator module:
If you were wondering why the VRM heatsink was so small, this is why. The Z77X-UD4 is a 9 phase motherboard, with a configuration of “6+2+1”. This means that the CPU core receives 6 phases, the memory controller and everything else on the CPU gets 2 phases, and the IGP gets the remaining phase.
You’ll also notice that while previous Gigabyte boards we’ve looked at have been using single chip “Driver MOSFETs”, the Z77X-UD3H uses a more traditional configuration, with each phase having a single high-side and low-side transistor, and a driver chip. Let’s take a closer look:
For most people, the CPU VRM on the Z77X-UD3H is more than sufficient for Sandy Bridge overclocking in the mid 4000 MHz range. Ivy Bridge might require more juice though, since it starts leaking power quickly as the heat ramps up, due to its horribly inefficient heat transfer plate interface.
In our overclocking tests, the VRM never went over 40 degrees celsius on an open bench, so even though the CPU Vcore phases aren’t 100% covered by a heatsink, the transistors themselves are cool. This is contrary to what we have seen with Driver MOSFETs while reviewing the Z68A-D3H-B3, which may be why Gigabyte switched back to a more traditional design.
Controlling the VRM is the PWM, an International Rectifier IR3567 chip. Until now, Gigabyte has almost exclusively uses analog PWMs on their Intel motherboards, but have gone fully digital with the 7-series. Analog vs Digital PWMs each have their advantages and disadvantages, but the main advantage of a digital PWM is how much control you can have over it. We’ll get to that when we look at the Z77X-UD3H software bundle.
Z77X-UD3H Motherboard Tour
As we continue our Motherboard Tour, we come to the audio chip. In this case, Gigabyte went with a Via chip, the 10-channel VT2021. It is your standard mid-range audio chip, with a 108 dB SNR for the output, and 100 dB input. You can read more about it on Via’s page. We’ll test its input and output quality later.
And here is the LAN controller, an Atheros AR8151 made by Qualcomm. Apologies for the low quality image – that is one tiny chip. You can read more about it here; we’ll look at performance later. One thing that stands out by now is that the Z77X-UD3H is a crab-free motherboard. That’s right, no Realtek this time…
Although the Z77 chipset supports four USB 3.0 ports, Gigabyte still added an auxiliary controller – again, an unexpected addition for this price range. The VL800 is a new one, made by Via Labs. It supports 4 ports in one chip, all of them going to the rear panel header. Note that unless you switch the xHCI to legacy mode, you will not be able to use these ports until drivers are installed. Read more about this chip here. Again, it will be interesting to see how this relatively new USB 3.0 solution performs.
As we often see with motherboards wanting to add an eSATA solution, they use an auxiliary SATA controller rather than give up one of the few lanes made available by the chipset. And as we often see with Gigabyte boards, a Marvell chip is used. This one is the Marvell 88SE9172, which you can read about here. Don’t expect much from it though – it is suitable as an eSATA solution, but its performance is too slow to use with high speed SSDs, even though it technically supports SATA 3.0. Both its ports are eSATA, so Gigabyte is aware of this fact.
Continuing with the themes of SATA connectivity and “things that don’t belong on a motherboard this affordable” is the integrated mSATA port. This allows you to install an SSD directly to the board itself, particularly smaller 32-64 GB modules that are perfect for using Intel’s Smart Response Technology (which is proven to significantly speed up a system when used, and is as good as other caching solutions).
One caveat with using this connection is that it uses a SATA 2.0 port, rather than SATA 3.0. If you want to use an mSATA drive and install it here, you will not reach the full potential performance that SSDs can offer. Still, even a moderate mSATA SSD using Intel Smart Response will be noticeably faster than using a mechanical drive by itself.
Although it’s getting long in the tooth perhaps, the iTE IT8782F SuperIO chip is still useful. One thing it does is add legacy connections, such as the COM port, and PS2 mouse/keyboard ports, printer port, etc. The Z77X-UD3H only makes use of the mouse/keyboard port in this case. Another important feature is its voltage and fan monitoring features. This is what allows you to use various monitoring programs such as OCCT or Gigabyte’s own software which we’ll look at later.
The second iTE chip is what gives the Z77X-UD3H its legacy PCI connectivity. It converts a single PCI-E lane to three PCI lanes, but the Z77X-UD3H only uses one of them. I don’t think the audio codec uses PCI, so the other two lanes will remain unused.
Finally, we come to Gigabyte’s bread and butter – Dual BIOS support. Unlike previous iterations, you can actually switch between the two chips at will, with a physical switch on board. This might come in handy for open bench overclocking, as you could have one chip with overclocked settings, and the other with default settings as a backup.
This concludes our Motherboard Tour. Let’s see what kind of software the Z77X-UD3H comes with.