Skip to main content

Gigabyte UD1000GM PG5 Review: The First PCIe Gen 5 Compatible PSU

The Gigabyte UD1000GM PG5 is the first PSU available on the market with a 12+4 pin PCIe connector.

Gigabyte UD1000GM PG5
(Image: © Shutterstock, Tom's Hardware)

To learn more about our PSU tests and methodology, please check out How We Test Power Supply Units. 

Primary Rails And 5VSB Load Regulation

The following charts show the main rails' voltage values recorded between a range of 40W up to the PSU's maximum specified load, along with the deviation (in percent). Tight regulation is an important consideration every time we review a power supply because it facilitates constant voltage levels despite varying loads. Tight load regulation also, among other factors, improves the system’s stability, especially under overclocked conditions and, at the same time, it applies less stress to the DC-DC converters that many system components utilize.

Load regulation is tight at 12V and 5VSB, and mediocre on the minor rails. 

Hold-Up Time

Put simply; hold-up time is the amount of time that the system can continue to run without shutting down or rebooting during a power interruption.

The hold-up time is at 17ms, aligning with the ATX spec's requirements. On the other hand, the power ok signal does not exceed 16ms. It is accurate, at least. 

Inrush Current

Inrush current, or switch-on surge, refers to the maximum, instantaneous input current drawn by an electrical device when it is first turned on. A large enough inrush current can cause circuit breakers and fuses to trip. It can also damage switches, relays, and bridge rectifiers. As a result, the lower the inrush current of a PSU right as it is turned on, the better.

Inrush current is not so high with 115V, but this not the case with 230V. 

Leakage Current

In layman's terms, leakage current is the unwanted transfer of energy from one circuit to another. In power supplies, it is the current flowing from the primary side to the ground or the chassis, which in the majority of cases is connected to the ground. For measuring leakage current, we use a GW Instek GPT-9904 electrical safety tester instrument.

The leakage current test is conducted at 110% of the DUT's rated voltage input (so for a 230-240V device, we should conduct the test with 253-264V input). The maximum acceptable limit of a leakage current is 3.5 mA and it is defined by the IEC-60950-1 regulation, ensuring that the current is low and will not harm any person coming in contact with the power supply's chassis.

Gigabyte UD1000GM PG5

(Image credit: Tom's Hardware)

Leakage current is low.

10-110% Load Tests

These tests reveal the PSU's load regulation and efficiency levels under high ambient temperatures. They also show how the fan speed profile behaves under increased operating temperatures.

Test12V5V3.3V5VSBDC/AC (Watts)EfficiencyFan Speed (RPM)PSU Noise (dB[A])Temps (In/Out)PF/AC Volts
10%6.516A1.969A1.98A0.993A100.0187.382%0<6.044.87°C0.963
12.032V5.08V3.332V5.038V114.44140.52°C115.13V
20%14.046A2.958A2.978A1.193A199.96390.554%0<6.046.17°C0.978
12.037V5.073V3.325V5.03V220.81441.08°C115.1V
30%21.954A3.454A3.479A1.394A300.01791.076%108533.341.79°C0.984
12.023V5.068V3.32V5.023V329.42147.64°C115.08V
40%29.834A3.953A3.984A1.595A399.74291.101%109133.542.15°C0.986
12.018V5.06V3.313V5.016V438.78748.38°C115.05V
50%37.368A4.949A4.992A1.797A499.47690.772%111033.843.21°C0.988
12.015V5.053V3.306V5.009V550.24649.85°C115.01V
60%44.972A5.949A6.004A2A600.01490.247%121636.243.58°C0.989
12.012V5.044V3.298V5.001V664.85750.59°C114.99V
70%52.516A6.953A7.022A2.203A699.76889.538%156142.043.73°C0.99
12.009V5.036V3.29V4.993V781.53151.42°C114.96V
80%60.136A7.96A8.042A2.306A799.80988.791%184345.544.62°C0.992
12.004V5.027V3.282V4.988V900.77252.67°C114.93V
90%68.091A8.473A8.55A2.409A899.63488.036%204448.244.98°C0.993
12.001V5.017V3.275V4.983V1021.91253.99°C114.9V
100%75.856A8.987A9.087A3.021A999.55887.325%212048.745.06°C0.994
11.995V5.008V3.268V4.966V1144.61955.15°C114.87V
110%83.543A10.003A10.212A3.023A1100.10186.507%213648.847.2°C0.994
11.992V4.998V3.261V4.963V1271.68958.05°C114.84V
CL10.116A14.813A14.96A0A126.29684.333%0<6.049.53°C0.969
12.042V5.083V3.315V5.05V149.76843.61°C115.12V
CL20.116A24.393A0A0A126.39283.338%0<6.050.84°C0.969
12.048V5.124V3.31V5.062V151.66244.01°C115.11V
CL30.116A0A24.823A0A83.88978.641%0<6.052.78°C0.962
12.040V5.04V3.323V5.043V106.67344.78°C115.13V
CL483.347A0.001A0A0.002A1000.08387.859%212648.745.81°C0.994
11.998V4.985V3.275V5.039V1138.27855.83°C114.87V

The PSU doesn't have a problem under harsh conditions, but don't expect it to be quiet. The passive operation lasted till 20% load in our tests, with the fan starting right away at almost 1100 RPM, which is too high. MEIC wants to ensure that the not-so-high quality caps on the secondary side will be ok under all conditions and outlive the warranty. 

20-80W Load Tests

In the following tests, we measure the PSU's efficiency at loads significantly lower than 10% of its maximum capacity (the lowest load the 80 PLUS standard measures). This is important for representing when a PC is idle with power-saving features turned on.

Test12V5V3.3V5VSBDC/AC (Watts)EfficiencyFan Speed (RPM)PSU Noise (dB[A])Temps (In/Out)PF/AC Volts
20W1.234A0.493A0.494A0.198A20.00371.113%0<6.040.04°C0.864
12.038V5.076V3.339V5.057V28.13136.81°C115.15V
40W2.717A0.69A0.692A0.297A40.00181.021%0<6.040.83°C0.921
12.032V5.075V3.338V5.055V49.37537.34°C115.15V
60W4.200A0.887A0.89A0.396A59.99985.095%0<6.042.28°C0.944
12.031V5.074V3.337V5.052V70.50438.4°C115.13V
80W5.680A1.084A1.088A0.495A79.95887.303%0<6.043.59°C0.951
12.030V5.074V3.335V5.049V91.58839.54°C115.13V

The fan doesn't spin at light loads, even at increased temperatures, so the PSU is silent. The efficiency levels are satisfactory, too. 

2% or 10W Load Test

From July 2020, the ATX spec requires 70% and higher efficiency with 115V input. The applied load is only 10W for PSUs with 500W and lower capacities, while for stronger units, we dial 2% of their max-rated capacity.

12V5V3.3V5VSBDC/AC (Watts)EfficiencyFan Speed (RPM)PSU Noise (dB[A])Temps (In/Out)PF/AC Volts
1.464A0.264A0.264A0.053A20.09971.259%0<6.029.52°C0.865
12.025V5.078V3.341V5.06V28.20627.36°C115.14V

With a 2% load, efficiency is above 70%, which is what the ATX spec recommends. 

Efficiency & Power Factor

Next, we plotted a chart showing the PSU's efficiency at low loads and loads from 10 to 110% of its maximum rated capacity. The higher a PSU’s efficiency, the less energy goes wasted, leading to a reduced carbon footprint and lower electricity bills. The same goes for Power Factor.

Even for the Gold standards, this platform is highly efficient in all load regions (high, low, and super-light). The APFC converter has decent performance. 

5VSB Efficiency

Test #5VSBDC/AC (Watts)EfficiencyPF/AC Volts
10.1A0.506W74.323%0.078
5.059V0.681W115.16V
20.25A1.265W78.783%0.167
5.056V1.605W115.15V
30.55A2.778W80.895%0.284
5.05V3.434W115.15V
41A5.042W81.319%0.366
5.04V6.199W115.15V
51.5A7.547W81.132%0.412
5.03V9.302W115.16V
63A15W79.311%0.47
5V18.913W115.15V

The 5VSB rail is highly efficient. 

Power Consumption In Idle And Standby

Mode12V5V3.3V5VSBWattsPF/AC Volts
Idle12.031V5.08V3.345V5.061V4.1420.369
115.15V
Standby0.1190.004
115.15V

Vampire power is increased. Ideally, it should be below 0.1W. 

Fan RPM, Delta Temperature, And Output Noise

All results are obtained between an ambient temperature of 37 to 47 degrees Celsius (98.6 to 116.6 degrees Fahrenheit).

(Image credit: Tom's Hardware)

(Image credit: Tom's Hardware)

The fan speed profile is aggressive. The compact dimensions of the PSU, the 120mm fans, and the low-grade caps on the secondary side don't leave room for lower fan speeds at high operating temperatures. 

The following results were obtained at 30 to 32 degrees Celsius (86 to 89.6 degrees Fahrenheit) ambient temperature.       

(Image credit: Tom's Hardware)

(Image credit: Tom's Hardware)

At average operating temperatures close to 30 degrees Celsius, the PSU is silent with up to 250W loads. The problem is that right after that, the PSU's noise exceeds 30 dBA. With around 680W, the fan's noise enters the 35-40 dBA range. With 750W, it goes above 40 dBA, and it passes the 45 dBA mark with around 930W loads. All in all, this is a noisy PSU. 

MORE: Best Power Supplies

MORE: How We Test Power Supplies

MORE: All Power Supply Content

Aris Mpitziopoulos
Aris Mpitziopoulos

Aris Mpitziopoulos is a Contributing Editor at Tom's Hardware US, covering PSUs.

  • Tom Sunday
    Greetings from LA. I love the idea in buying one of these when the time or my ship finally arrives! Another new PSU. Out with the old and in with the new! But when I 'tanked-up' this early morning at $7.95 per gallon in Beverly Center…I did not even have enough cash in completely filling-up! Next payday is a week away! Even my daily lunchbox meal increased by about 50% and I already gave-up drinking Mountain Dew all-together. Before all of this inflation mess started I regularly came to visit most of the major tech-channels to dream about all of the fine and newly proffered hardware. About the absolute "must haves." It appears that my dreams are now over and perhaps a nightmare is settling-in for the man on the street like me! I cannot help thinking that there must be many more people like me in the same boat facing a new reality!
    Reply
  • Udyr
    So this is a 4 star product with 1, 2, 3, 4... 12 cons?

    The cons are somewhat consistent with the review on TPU, but over there it was not a recommended product.

    Maybe there's something more my ignorant self is not seeing here.
    Reply
  • DRagor
    Udyr said:
    So this is a 4 star product with 1, 2, 3, 4... 12 cons?
    The Gigabyte UD1000GM PG5 is the first PSU available with a 12+4 pin PCIe connector, so practically, it doesn't have any competitors yet.
    How it was? In the land of blind one eyed is a king?
    Reply
  • WrongRookie
    No thanks. I'd rather wait for Seasonic do one than get another one that could end up exploding
    Reply
  • Udyr
    DRagor said:
    How it was? In the land of blind one eyed is a king?
    I understand the reference, but in this case, a unit with these many downsides doesn't justify a recommendation, unless there's something else besides being the only one available (for now).
    Reply
  • thisisaname
    Udyr said:
    So this is a 4 star product with 1, 2, 3, 4... 12 cons?

    The cons are somewhat consistent with the review on TPU, but over there it was not a recommended product.

    Maybe there's something more my ignorant self is not seeing here.
    Some of the positives are not that great either.
    +Full power at 47 degrees Celsius
    +Most protection features are properly set
    Reply
  • watzupken
    Once beaten, twice shy. After the shady practice and persistent denial of critical flaws with their product by Gigabyte, even if this is a 5 stars PSU, I will not bother to consider it. There are much better options out there. I rather pay more than to deal with shady companies. In my opinion, it is not the product that we need to be mindful because every company will at some point produce bad product. It is how they take steps to resolve the issue and maintain that goodwill. Gigabyte basically burned that goodwill in the PSU fiasco. So no more Gigabyte products for me since the company can’t be bothered.
    Reply
  • Tom Sunday
    A few thoughts to catch-up! Most of the PSU’s are made by a small group of manufacturers, and resellers simply buy those manufacturers PSU's and then rebrand them as their own products. I usually buy SeaSonic because pure and simple they are a manufacturer. They make all their own PSU’s and sell them to consumers besides the best RMA service in the industry! So going with a SeaSonic PSU is almost certainly to be a safe bet. I also found that resellers generally offer three to five-year warrenties on their PSU's, and Seasonic offers in many cases five to twelve-year waranties. This alone tells the story and in how much confidence the reseller usually has towards its selected manufacturer.

    In turn CORSAIR as an example is a true reseller, not a manufacturer. This can be a big deal. They buy their PSU’s from their original manufacturers so the quality of their products ultimately depends on their original manufacturers or perhaps those manufacturers which returned the lowest fabrication bid on a large CORSAIR factory order. It can be difficult to find out where CORSAIR’s PSU’s come from as CORSAIR has routinely been using 3-5 different manufacturers and in diffrent countries. In time likes these where high wattage and or premium PSU’s (1200W-1600W) may easily exceed $400 plus to especially feed the upcoming 4000 series GPU craze, picking the right PSU becomes important! As one of the dealers at the recent computer show noted: “SeaSonic principally specializes in PSU’s while CORSAIR markets and sells hundreds of different products. “Go take your pick!”
    Reply