The Gigabyte UD1000GM PG5 1000W PSU Review: Prelude to ATX 3.0

Hot Test Results (~45°C Ambient)

Despite its lengthy warranty, the components of the UD1000GM PG5 left us unimpressed and our testing verified our initial assumptions. The PSU suffers when it has to operate inside a very hot environment, with the efficiency taking a brutal drop at high loads. The average efficiency reduction of 1% across the nominal load range does not seem that high but the efficiency drop is very high when the load is greater than 800 Watts, suggesting severe thermal stress.

Despite the very high ambient temperature, the fan of the GIGABYTE UD1000GM PG5 failed to start right away with the unit operating inside our hotbox. This resulted to worryingly high temperature readings at low loads. Once the fan started, the temperature dropped significantly, rising little by little as the load increased. The temperature does reach high figures again once the unit is heavily loaded but always stays within operating levels.

Even though it does not start right away, as expected, the 120 mm fan is giving its all to keep the GIGABYTE UD1000GM PG5 cool enough under these adverse operating conditions. The very moment is starts, the fan will be audible to the user, rapidly increasing in speed as the load increases. It reaches its maximum speed when the load is just a little higher than 50% of the unit’s capacity, valiantly trying to keep the PSU reliable and operational. The noise figures are above 50 dB(A), a figure that will annoy even the most tolerant of people if they are not wearing headphones – or ear protection.