Last night there was a sudden power surge at my place, and it fried the power supply unit (PSU) in my custom desktop. I replaced the PSU with a new one of the same wattage and brand, but now the PC won’t boot unless the GPU is installed. Before the surge, I could run with integrated graphics just fine since my CPU supports it. I double-checked all connections, reseated the CPU and RAM, and even reset CMOS to clear any BIOS hiccups. The motherboard powers on (LEDs light up), fans spin, but no POST beeps or display output without the GPU. Plugging in the GPU brings everything back to normal. Is it possible the power surge damaged the integrated graphics on the CPU or some motherboard circuitry? Or maybe the BIOS got corrupted in a way that disables integrated video? Has anyone seen something like this? What would you test next to isolate if it’s the CPU, motherboard, or just a weird PSU compatibility issue? Any creative troubleshooting ideas appreciated!

That power surge definitely could have damaged the integrated graphics on your CPU or even some motherboard components responsible for video output. Since your system only boots with the GPU installed, it sounds like the iGPU path might be fried or disabled at a hardware level. You mentioned resetting CMOS, which usually resets BIOS settings, but if the BIOS itself got corrupted, reflashing it might help - check if your board supports BIOS flashback without a CPU installed.

Another angle is to test with a different CPU if you can, to isolate whether the CPU’s iGPU is toast. Also, try a different PSU just to rule out any subtle compatibility or power delivery issues, even if it’s the same brand and wattage. Sometimes PSUs have quirks that only show up under certain loads or configurations. If you have onboard video connectors on the motherboard, double-check those pins and connectors for any physical damage from the surge.

It’s a frustrating spot to be in,

On 02/27/2026 at 3:20 PM, hikerkind said:

Last night there was a sudden power surge at my place, and it fried the power supply unit (PSU) in my custom desktop. I replaced the PSU with a new one of the same wattage and brand, but now the PC won’t boot unless the GPU is installed. Before the surge, I could run with integrated graphics just fine since my CPU supports it. I double-checked all connections, reseated the CPU and RAM, and even reset CMOS to clear any BIOS hiccups. The motherboard powers on (LEDs light up), fans spin, but no POST beeps or display output without the GPU. Plugging in the GPU brings everything back to normal. Is it possible the power surge damaged the integrated graphics on the CPU or some motherboard circuitry? Or maybe the BIOS got corrupted in a way that disables integrated video? Has anyone seen something like this? What would you test next to isolate if it’s the CPU, motherboard, or just a weird PSU compatibility issue? Any creative troubleshooting ideas appreciated!

Sounds like that surge really did a number on your setup. Since the motherboard powers on but won’t POST without the GPU, I’d lean toward the integrated graphics on the CPU or the motherboard’s video output circuitry being damaged. Sometimes the integrated GPU can survive power issues, but the supporting VRMs or traces on the board might not.

One thing you could try is to flash the BIOS with a fresh copy from a USB stick, just in case the surge corrupted the firmware and disabled onboard video. If you have access to another compatible CPU, swapping it in could help isolate whether the CPU’s graphics are toast or if it’s the motherboard. Also, if your motherboard has a debug LED or speaker, check for any error codes or beep patterns that might hint at GPU or video initialization failures.

It’s a rough spot, but if you can confirm the CPU’s integrated graphics are dead, running with a discrete GPU might be your only option now. Otherwise

On 02/27/2026 at 3:20 PM, hikerkind said:

Last night there was a sudden power surge at my place, and it fried the power supply unit (PSU) in my custom desktop. I replaced the PSU with a new one of the same wattage and brand, but now the PC won’t boot unless the GPU is installed. Before the surge, I could run with integrated graphics just fine since my CPU supports it. I double-checked all connections, reseated the CPU and RAM, and even reset CMOS to clear any BIOS hiccups. The motherboard powers on (LEDs light up), fans spin, but no POST beeps or display output without the GPU. Plugging in the GPU brings everything back to normal. Is it possible the power surge damaged the integrated graphics on the CPU or some motherboard circuitry? Or maybe the BIOS got corrupted in a way that disables integrated video? Has anyone seen something like this? What would you test next to isolate if it’s the CPU, motherboard, or just a weird PSU compatibility issue? Any creative troubleshooting ideas appreciated!

Sounds like that power surge really threw a wrench in the works. Since your system only boots with the GPU installed, it’s quite possible the integrated graphics on your CPU took a hit, or the motherboard’s video output circuitry got damaged. Even if the CPU itself seems fine otherwise, the integrated GPU can be fried separately.

One thing you might try is to update or re-flash the BIOS with a fresh copy from the motherboard manufacturer’s site - sometimes BIOS corruption can cause weird behavior like this. Also, if you have access to another compatible CPU with integrated graphics, swapping it in could help isolate whether the CPU or motherboard is at fault.

Lastly, double-check that the new PSU is delivering stable power on all rails, especially the 12V line feeding the motherboard and CPU. Even if it’s the same brand and wattage, a faulty or incompatible PSU can cause strange boot issues. If you have a PSU tester or a friend with a spare