I bought a Corsair HX750 more than 15 years ago for a system with an AMD FX processor and two Radeon 7870s in CrossFire. It has been used daily through an AM3+ system upgrade to AM4, survived several voltage surges, and has never shown obvious problems such as blown capacitors or unstable output. I am now considering moving to an AM5 build with an Asus B650M-A motherboard, Ryzen 9 9900X, 64 GB of DDR5-6000 memory, an Asus GeForce RTX 3070 Ti, and several extra USB and card-reader devices. Should I continue using this PSU, or is replacing it the safer choice?
5 Answers
One other consideration is the CPU choice: the Ryzen 9 9900X can make sense if the price is especially good or you need its extra cores, but it is not dramatically faster for gaming than lower-tier Ryzen 9000 chips. Since this processor is refurbished, make sure the discount justifies the cost and that it includes adequate testing or a return period.
The old HX750 was a high-quality model, and the RTX 3070 Ti does not require the newest high-power connector, so it might still run the system electrically. However, age matters more than the fact that it has not failed yet. Since you plan to keep the replacement for many years too, choosing a modern model with a long warranty—such as a good higher-end unit with a 10- or 12-year warranty—would make more sense.
I would not risk a 15-year-old PSU in a new, expensive computer. An aging power supply may cause boot problems, crashes, or instability before it visibly fails, and in the worst case it could damage other components. Spending roughly the equivalent of $80–$100 on a well-reviewed modern PSU is a worthwhile safety margin.
I would use the warranty period as the practical limit. Even excellent power supplies usually have warranties around 10–12 years, so a unit that is over 15 years old is well past its expected service window. Newer models also generally have improved protections and safety standards.
Replace it. A PSU can keep working while its capacitors and other internal components gradually degrade. Surviving previous surges is encouraging, but it does not prove the unit still has its original capacity or protection performance. A modern, reputable 750–850 W unit is relatively inexpensive insurance for an expensive new build.
I would not assume the PSU has literally lost a fixed percentage of its wattage every year, but its aging capacitors can reduce reliability and transient performance. The exact remaining capacity is difficult to know without proper testing.