Power Issue When Running Games On Windows

I also have this issue with my late 2012 iMac in Windows 10. Happens on certain games. I thought it was because of the GPU getting too hot but it happens sometimes as the game as loaded, before the GPU even gets warm.

The iMac just shuts off instantly. It's done it in macOS also.

Did you ever find a fix?

I guess its either the PSU, or maybe the HDD recall issue (I never got chance to take mine back to be replaced).

Pugberto wrote:

Once the power is out, the iMac won't restart unless I remove the plug and put it back in the power outlet.

Does your surge protector have current limiting features? This can also indicate that the PSU in the iMac is failing. If there are other devices plugged into the Surge Protector, do they stay on, even when the iMac cannot restart?

You will have to look at the ratings and features of the surge protector. You can try a SMC reset - Resetting the System Management Controller (SMC) on your Mac - Apple Support - to see if it addresses your power issue.

It depends on how many devices it is protecting. It seems to be very reasonable. Since you have tested using wall outlets, the surge protector is not as significant as the other iMac power issue. Does the same behavior occur when plugged into wall socket. If yes, then the SP is not an issue.

Can you run a Apple Hardware Test on the iMac - Using Apple Hardware Test - Apple Support? It may not catch all issues, but it is good start.

If AHT did not reveal anything, my suspicion is that the PSU is failing. You can look at iFixit web site for you model and see the PSU.

Destructive surges are hundreds of thousands of joules. Those spec numbers define a near zero protector.

However you have zero reasons to suspect a surge. A surge means hardware damage - a computer no longer boots. You have defined symptoms of something completely different and unrelated.

Best protection at the computer is already inside a computer. You have described what may be a protective lock out feature. Other anomalies (some from AC mains) may trigger that lockout. The lockout can only be cleared by a complete disconnect from AC mains.

Meanwhile, anomalies that might trigger that lockout are completely ignored by that protector. Take another spec number from its box. Its let-through voltage may be 775 volts. That means the protector does absolutely nothing until 230 volts well exceeds 775 volts. If that situation exists, you are also replacing other damaged appliances such as refrigerator, smoke detectors, dishwasher, GFCI or RCD, clocks, or CFL light bulbs.

List of other suspect that might cause those symptoms are long. And none are averted by a power strip protector.

Is voltage too low? Attach a light bulb to the same power strip. Normal voltage is even when an incandescent bulb dims to 40% intensity. Does that light bulb dim? If not, also ignore recommendations that 'fear' voltage problems.

Thanks, westom. Very clearly articulated.

Thermal protection should also be factored in. If the heat sink to IC connection is not good (thermal paste breakdown), you should have it looked at.