Gigabyte GA-P55M-UD4: Short Review of a Small Good Mainboard

Today we will talk about another small but fully functional microATX mainboard that can easily compete against some ATX solutions and can is even superior to some in functionality and features. It is based on Intel P55 Express chipset, supports LGA1156 processors and is called Gigabyte GA-P55M-UD4.

by Doors4ever
01/15/2010 | 02:37 PM

A lot of computer enthusiasts are very skeptical, even contemptuous, towards microATX mainboards. These solutions are considered to be de facto inferior to full-size ATX mainboards in their functionality, number of onboard controllers, fine tuning and overclocking options. Therefore, most microATX mainboards usually find their way into office workstations and at best the lowest end home systems. I have to say that this attitude appeared for a reason, but lately things started to change. New microATX mainboards appeared that allowed to put together a very powerful gaming or computational workstation even inside a small system case. And the perfect examples of this tendency are right here at the tip of your fingers: take, for instance, Asus Rampage II Gene and DFI LanParty JR X58-T3H6, which are barely yielding to their full-size ATX sisters.


Today we are going to talk about the features and performance of another small but fully-functional microATX mainboard that can easily compete even against some ATX solutions and proves superior to some of them in functionality. It is built around Intel P55 Express chipset, supports LGA1156 processors and is called Gigabyte GA-P55M-UD4.

Package and Accessories

All boxes for Gigabyte Intel P55 Express based products have similar design theme, the only difference is in the colors they use. For example, the dominating color for the UD4 mainboard series, including Gigabyte GA-P55M-UD4, is green.

Inside the box you fine the mainboard in an antistatic bag alongside with the following accessories:

PCB Design and Functionality

Gigabyte GA-P55M-UD4 mainboard is very small: it will fit into a square with sides less than 25 cm long. However, it is very heavy just like all contemporary Gigabyte mainboards using 2 oz copper PCBs. The more you look at this mainboard, the more you get amazed with the developers talent to fit such an enormous number of components onto a small PCB surface like that. The small Gigabyte GA-P55M-UD4 features absolutely everything a contemporary mainboard should have.

I believe I should start with the processor voltage regulator circuitry. This circuitry is based on contemporary component base and consists of twelve phases. The number of voltage regulator phases may change dynamically depending on the current CPU utilization level. A special row of LEDs will show you the number of currently active phases in the converter at all times. All power connectors on Gigabyte GA-P55M-UD4 are very conveniently located, there is enough free room around the processor socket to fit even large CPU coolers normally. For example, we didn’t have any issues with a pretty large Cooler Master GeminII cooler we used during our test session.

Despite limited PCB space, Gigabyte GA-P55M-UD4 managed to retain its FDD connector, and PATA support on it is provided by an additional Gigabyte SATA2 controller. Thanks to this controller there are also two white SATA connectors. Next to them you can see another four SATA connectors in the same vertical stacks and one more a little farther away in the back. All these five connectors receive SATA support from the chipset, while the sixth one is laid out on the mainboard back panel in the form of a combination eSATA/USB port.

Besides eSATA/USB on the back panel, Gigabyte GA-P55M-UD4 also has a combination PS/2 connector for keyboard or mouse, ten USB ports (including the above mentioned eSATA/USB). Four more USB ports are available as onboard pin-connectors on the PCB. Optical and coaxial S/PDIF as well as six analogue audio-jacks are supported by eight-channel Realtek ALC889A codec. Network adapter is based on Realtek RTL8111D Gigabit controller, IEEE1394 (FireWire) port is implemented via Texas Instruments TSB43AB23 controller and one more port is available as an onboard pin-connector as well.

When we list all the features of Gigabyte GA-P55M-UD4 mainboard we can’t help mentioning that it supports not only ATI CrossFireX graphics card configurations, but also Nvidia SLI. Therefore, there are two PCI Express x16 connectors on the board. When there are two graphics cards installed into the system, these connectors switch to x8/x8 mode. The board has Power On, Reset and Clear CMOS buttons. Power On button glows and also serves as an indicator that the board receives power. There are four fan connectors, which is a very good number for a small mainboard like that. Like all other contemporary Gigabyte mainboards, GA-P55M-UD4 also supports Dual BIOS technology and has two corresponding chips onboard.

I believe we haven’t missed anything when we listed the features of Gigabyte GA-P55M-UD4 mainboard, but just for the sake of it, let me offer you the official specification sheet:

Here I would like to add that Gigabyte GA-P55M-UD4 also boasts Gigabyte’s typical little bonuses that make working with this board a lot more fun. For example, color coding and polarity indication for front panel buttons and connectors as well as markings not only next to the USB and IEEE1394 (FireWire) ports but also inside them.

Surprising as it might seem, but relatively small size of Gigabyte GA-P55M-UD4 didn’t prevent the developers from making it extremely functional and featuring a lot of additional controllers. Moreover, the PCB layout looks very convenient and smart, it is very pleasant to work with, which sets things off on a positive note right from the start.

BIOS Setup

Gigabyte mainboards have one distinguishing feature: the basic BIOS functionality of flagship and low-end mainboards is hardly different. When you check out the BIOS of Gigabyte GA-P55M-UD4, you won’t have any reason to believe that it is a small microATX mainboard: everything is pretty “serious” here. We have already discussed in great detail the BIOS functionality of LGA1156 mainboards from Gigabyte in our Gigabyte GA-P55-UD6 review. You can find all BIOS screenshots without any exceptions in our Gigabyte GA-P55-UD3R review, but without the detailed comments of ours. So, this time we will quickly look through the major BIOS sections to refresh your memory a bit. I would like to remind you one more time that you must press Ctrl-F1 from the main menu of Gigabyte BIOS Setup in order to get full access to all available parameters and settings.

It is very convenient that the first on the list is “MB Intelligent Tweaker (M.I.T.)” section with the most important parameters for system overclocking and maximum performance optimization. However, the first screen only opens the list of available sub-sections for you and reports the basic system information.

You can set more details about the current system parameters in “M.I.T. Current Status” sub-section:

“Advanced Frequency Settings” sub-section will allow you to adjust frequencies, multipliers and dividers.

It is very convenient that the CPU related settings are all singled out on a separate page.

Almost all parameters are set to Auto that is why you should be careful when you change the operational settings significantly, like during overclocking, for instance. In this case the board may decide to enable or disable certain functions and technologies, which may cause some problems. It would be better to set the parameters to “Enabled” or “Disabled”.

“Advanced Memory Settings” sub-section allows fine tuning memory sub-system parameters.

Memory timings can be changed on a separate page. You can set memory timings for each channel individually or for both at the same time.

“Advanced Voltage Settings” sub-section offers options for voltage adjustment.

“PC Health Status” section doesn’t impress us with too many options or information. However, it is very nice to see that it retained Gigabyte’s ability to automatically adjust the rotation speed of four- as well as three-pin processor fans.

The only thing we should remind you of, is that you can launch Q-Flash utility for BIOS updating by pressing F8, and with F11 and F12 keys you can save and quickly load eight complete BIOS settings profiles. You can assign a memorable name of your own to each of these profiles, you can save each of them on an external storage medium. Moreover, the mainboard would automatically save a couple of last known good configurations, when the mainboard booted successfully.

Overall, the BIOS functionality of Gigabyte GA-P55M-UD4 is extremely good. The board has everything you might ever need, and even if there are certain drawbacks, they are uncritical and insignificant.

Testbed Configuration

We performed all our experiments on the following test platform:

We used Microsoft Windows 7 Ultimate (Microsoft Windows, Version 6.1, Build 7600) operating system, Intel Chipset Software Installation Utility version, ATI Catalyst 9.9 graphics card driver.

Operational and Overclocking Specifics

When we studied the BISO functionality we didn’t notice any significant changes or new parameters. However, work on the BIOS never stops and it is not limited to fixing the emerging issues or adding new processors support. Note that the latest BIOS version we tested the board with is F5. As soon as Gigabyte GA-P55M-UD4 board booted for the first time we learned about the changes that had been introduced by then. By default hard drives work in compatibility mode. However, we were immediately offered to switch them into AHCI (Advanced Host Controller Interface) mode in order to fully use the advantages of our Serial ATA drives. You can agree to this by pressing “Y” key or disagree by pressing the “N” key. Any other key stroke will continue the booting process. If you stepped away from your system, nothing bad is going to happen: the OS will still boot when the timer runs out. A very interesting innovation, I should say.

The second piece of good news is that Gigabyte mainboards, at least Gigabyte GA-P55M-UD4, stopped raising their base clock. We do understand the reasons behind this raise: to ensure that during performance comparison in nominal mode Gigabyte mainboards could be at least a little bit faster than their competitors. Unlike ASRock P55 Deluxe mainboard, Gigabyte boards allowed you to easily drop the base clock back down to its official nominal 133 MHz. But now this frequency is set by default.

However, not the entire test session was as nice and easy as its beginning. We did experience some problems during CPU overclocking attempts. I have to remind you that we have already discussed the basics, terminology and approximate overclocking algorithms in our earlier article called “Guide: Lynnfield Overclocking on Asus P7P55D Deluxe Mainboard”. Of course, we mostly focused on Asus P7P55D Deluxe mainboard and Intel Core i7-860 processor, but the basic overclocking principles typical of LGA1156 platform are the same on every mainboard and you will easily find the corresponding equivalents among the parameters of your mainboard and CPU.

We managed to have the system pass our preliminary tests at 210 MHz base clock with the lowered processor clock frequency multiplier, like we did on most other mainboards. However, we had to crank up the voltage on the memory controller integrated into the CPU (IMC) to 1.37 V, which is very high, because the nominal IMC voltage is only 1.1 V. Luckily, we didn’t need to push the base clock frequency so high up to overclock our processor to its maximum, so Gigabyte GA-P55M-UD4 mainboard could relatively easily hit 3.95 GHz CPU speed. I say “relatively” because we had to increase the processor core voltage a little higher than usual, so that it hit 1.328 V under maximum load, as you can see from the screen shot below.

Until now only two Gigabyte mainboards – GA-P55-UD6 and GA-P55-UD3R – as well as Asus P7P55D Deluxe could overclock the CPU that high that is why it is extremely pleasing to see our small Gigabyte GA-P55M-UD4 solution joining this elite group so easily.

Now all Intel processor power-saving technologies stay up and running on Gigabyte mainboards even when you overclock by raising the processor core voltage. It means that the CPU clock frequency multiplier as well as Vcore will lower in idle mode.

Performance Comparison

Time has come to check out the performance numbers and compare the results in two different system modes: in nominal mode and during CPU and memory overclocking. First we are going to talk about the results in nominal mode, when the boards set the most optimal parameters on their own, almost without any help from the user. Due to Intel Turbo Boost technology the clock frequency multiplier of our Intel Core i7-860 processor could increase to 26x. Our today’s hero will be competing against previously tested LGA1156 mainboards. The mainboards are listed on the diagrams according to their performance (from high to low). The results of Gigabyte GA-P55M-UD4 mainboard are marked with a darker color for your convenience.

In order to estimate the results of Gigabyte GA-P55M-UD4 mainboard correctly, we have to remind you that two previously tested Gigabyte mainboards increased the base clock in nominal mode, but ASRock P55 Deluxe board increased this setting even more. That is why these solutions were faster than everyone else. Biostar TPower I55 mainboard also had peculiarities of its own: even with Turbo technology on it didn’t always increase the CPU clock frequency multiplier, which often led to the lowest scores in the nominal mode. So, the only mainboards working in the same conditions as Gigabyte GA-P55M-UD4 are the ones from Asus, DFI LANPARTY DK P55-T3eH9 and Intel DP55KG, therefore you should take their performance numbers into account in the first place.

Even despite all corrections and additions, the results of Gigabyte GA-P55M-UD4 in the nominal mode do not look their best, but this is a very deceiving impression. Most often we see the board at the bottom of the list and once it was even the very last one. However, if we compare the numbers, we will notice that the difference is often very small. In nominal mode Gigabyte GA-P55M-UD4 mainboard performs perfectly fine.

The second comparison was performed during maximum processor overclocking. This time we disabled extended processor power-saving modes in the mainboard BIOS using “C-STATE” parameter, which limited the maximum processor clock frequency multiplier setting with 22x. In this case the CPU could work at higher base clock than with 26x multiplier, which meant that we ended up with higher resulting performance although it happened at the expense of higher power consumption in idle mode. During the performance tests with overclocked CPU and memory the boards were also split into two groups. Only Gigabyte mainboards and Asus P7P55D Deluxe could overclock our processor to 3.95 GHz, while all others stopped at 3.9 GHz.

As you can see, the situation has changed completely during overclocking. Gigabyte GA-P55M-UD4 mainboard is at the top of the performance charts and even takes the lead once. But if we look at the actual numbers one more time, we will see that there is nothing extraordinary about its results: it demonstrates normal performance level for a system with overclock processor and memory. So, overall, the performance of Gigabyte GA-P55M-UD4 mainboard in nominal mode as well as during overclocking doesn’t really surprise us: it is at about the same level as by other mainboards.

Power Consumption

We measured power consumption using Extech Power Analyzer 380803 device. This device was connected before the system PSU, i.e. it measured the power consumption of the entire system without the monitor, including the power losses that occur in the PSU itself. When we took the power readings in idle mode, the system was completely idle: there were even no requests sent to the hard drive at that time. We used LinX program to load the Intel Core i7-860 CPU. For more illustrative picture we created a graph showing the power consumption growth depending on the increase in CPU utilization as the number of active computational threads in LinX changed in nominal mode as well as during overclocking. Besides Gigabyte GA-P55M-UD4 we also included the results of all previously tested LGA1156 mainboards. The boards are sorted out in alphabetical order on the diagrams below.

The small Gigabyte GA-P55M-UD4 doesn’t consume too much energy. Depending on the operational mode, its power consumption is either about the same as that of other pretty energy-efficient solutions, or even a little lower. Well, this is definitely another argument in favor of Gigabyte GA-P55M-UD4.


If you look back at our today’s review, Gigabyte GA-P55M-UD4 didn’t give us a single reason to be upset or annoyed about anything. It is small in size, but boasts very smart design and has all the features typical of contemporary Intel P55 Express based mainboards. It has a complete set of BIOS options for performance optimization and overclocking fine-tuning. Moreover, the board put all its abilities to good use and overclocked our test CPU to its maximum, which far not all full-size mainboards can achieve. Gigabyte GA-P55M-UD4 performs at a normal level in nominal mode as well as during CPU and memory overclocking. Its power consumption is at about the same level as that of other pretty energy-efficient solutions, or even a little lower than that. So what would be the final verdict for this board? Of course, an excellent one!

Gigabyte GA-P55-UD3R mainboard also received our praises, but we did point out that some users could be unhappy about the fact that it didn’t support Nvidia SLI and didn’t have an additional IEEE1394 (FireWire) controller. Gigabyte GA-P55M-UD4 has it all and also offers a combination eSATA/USB port on the back panel. Amazingly, all that fits into a small form-factor. Of course, if the size of the board is your primary criterion, then you could also check out another small and even less expensive Gigabyte GA-P55M-UD2 mainboard. Of course, the more choices there are, the better it is for the consumer, that is why it is really great to see so many different Gigabyte mainboards to be on top of our preferences list lately.