I reset and reinstalled Windows 11 on my Omen desktop, which has an i7-9700F, 16 GB of DDR4-3200 RAM, a GTX 1060, and a Corsair 600 W power supply. The system has two SSDs and one HDD containing important files. I disconnected the HDD before reinstalling Windows and reconnected it only after the installation and drivers were complete.
After reconnecting the HDD, the computer briefly started and then shut off completely. Since then, it powers the fans and LEDs but does not reach the BIOS or produce video output. Removing the graphics card caused beep codes, and trying another graphics card produced similar beeps with no display. Clearing the CMOS changed the beep pattern, and reseating the RAM and graphics card temporarily allowed the computer to boot normally. However, reconnecting the HDD caused the same no-display problem to return.
What should I test next to determine whether the problem is the HDD, its cables, the power supply, the motherboard, or a loose component? I want to recover my files and repair the PC without replacing the whole system.
2 Answers
Start with a bare-minimum POST test. Turn the PC off, unplug it, and disconnect the HDD completely, including both SATA data and power. Also disconnect any unnecessary USB devices. Leave only the motherboard, CPU, one RAM stick, graphics card, boot SSD, keyboard, and monitor connected. Try each RAM stick individually and use the recommended slot from the motherboard manual.
A power-supply voltage check with a multimeter does not prove that the PSU is healthy under load. The HDD, its SATA power lead, or a damaged connector could be pulling down a power rail, but the PSU, motherboard, or graphics-card power connection could also be failing. Do not reconnect the HDD until the computer can consistently reach the BIOS with the minimum setup.
The HDD should not normally prevent a system from reaching the BIOS, so first confirm whether the machine can POST with every drive disconnected. If it does, reconnect the HDD using a different SATA data cable, a different motherboard SATA port, and a separate SATA power connector if the PSU has one. Never connect or disconnect internal SATA cables while the PC is powered on.
If connecting that specific drive immediately brings back the failure, stop repeatedly powering it on. The drive or its power circuitry may be faulty, and repeated attempts could make data recovery harder. Since the files are important, test the drive in another known-good computer or use a SATA-to-USB adapter only if the drive does not show signs of electrical failure. Copy the important data before attempting repairs.
Also inspect the SATA power plug and the drive’s connector for bent, loose, or burned contacts. If the computer fails even with all drives disconnected, focus on POST hardware instead: one RAM stick at a time, the GPU and its power lead, CMOS settings, PSU, and motherboard.
The fact that reseating the RAM or GPU temporarily changed the result may indicate a loose connection or a board that is right on the edge of failing, rather than Windows being the cause. Check that the 24-pin motherboard cable, CPU power cable, GPU power cable, and RAM are fully seated.