I tried overclocking the memory in my OMEN by HP 25L Gaming Desktop (GT15-Oxxx, 89EB motherboard) by setting it to 3400 MHz, CL15, tRCD/tRP 17, and 1.350 V. After saving the settings, the computer shut down and now powers on without completing POST. The monitor and keyboard receive no signal, the GPU lights up, and the case fans spin, although the PSU fan remains off. I tested each RAM stick separately, removed the CMOS battery for 15 minutes, used the CMOS jumper, and reseated the GPU, but nothing changed. Two technicians were unable to resolve it and suggested different causes. What should I try next, and could the BIOS, memory controller, RAM, or motherboard have been damaged?
4 Answers
If a proper CMOS reset and known-good RAM do not restore video, the firmware may be stuck or corrupted. An EEPROM programmer or BIOS reflash could potentially recover it, but that usually requires a repair shop with the right equipment. Avoid repeatedly changing settings without a way to recover the firmware.
The memory settings may simply be too aggressive for this OEM motherboard or CPU. Use the slowest, known-supported memory configuration possible and test with one module at a time. The fact that the fans and GPU light up only confirms that the system receives power; it does not mean POST is completing.
HP does not provide much public documentation for that motherboard, so component testing is probably the most reliable next step. Since the Ryzen 5 5600G has integrated graphics, remove the dedicated GPU and connect the monitor to the motherboard video output. If there is still no POST, test with known-good RAM, power supply, and—if available—another compatible CPU or motherboard. The PSU fan not spinning by itself is not conclusive, since many power supplies keep their fan off at low temperatures.
Try a complete CMOS reset rather than only removing the battery. Turn the PSU switch off, unplug the power cable, hold the case power button for at least 10 seconds to discharge the system, then short the clear-CMOS pins according to the motherboard instructions. Reinstall one known-good RAM stick and try booting again.
I did remove the battery and use the jumper, but I’ll repeat the process with the PSU disconnected and the system fully discharged.
Resetting the BIOS normally fixes a memory-only issue, so if that was done correctly and tested RAM makes no difference, the motherboard firmware or memory controller becomes more suspect.