Question CPU turns on but no output in Monitor, Keyboard and Mouse

[Bharath Ulaganathan]

Specs:
i5-6500
Asus H110M-D
iGPU (HD 530)
8GB DDR4 RAM
WD 2TB HDD
Zebronics 450W PSU

When I power on the PC, CPU fan turns on and LED in the Motherboard turns on, other than that there is no output to any peripherals (Monitor, Keyboard, Mouse). I think the HDD also is getting power as restarting the PC gives a sound from the HDD. For some odd reason, the Chassis fan powered directly by the PSU is not working. Might be it died as it was running noisy for months.

Things I have tried

• Cleared CMOS data by removing the battery and using the clear CMOS jumper. Also replaced the CMOS battery.
• Swapped to a new PSU.
• Checked the 24 pin ATX connector power output and it is all in check.
• Turned on with nothing other than just the RAM.
• Tried powering on even without the RAM (by mistake) and there was no beep sound at all (the speaker wire to motherboard is connected)
• Cleaned and swapped the RAM to the other slot.
• Cleaned the CPU socket and reapplied thermal compound for the CPU fan.

Nothing seems to help. Is the motherboard dead? Is there any other thing I could do to confirm or troubleshoot the problem?

The problem started 2 weeks ago when the PC randomly started rebooting without any blue screen. I tried to run RAM test using a software from USB directly from BIOS and it was rebooting even in that setup. I tried to startup in safe mode to test all components (CPU GPU stress test, RAM test, HDD S.M.A.R.T. test) and the PC didn't reboot even once in 2 hrs. Booted back to Windows and miraculously everything stayed stable for 1 week. Last week, when I turned the PC back on from 2 hrs of hibernation, the fan turned on but no other output. I let it be for a while and later checked it again and the issue persisted. I tried reinstalling the RAM and replacing the CMOS battery but nothing solved the issue. After 2 days of being away from the PC, it booted to a screen showing all parts Installed and asked Me to continue to BIOS to setup but no action from the keyboard worked (the LED on the keyboard was on). Restarting again made no progress as no keyboard action worked. Third restart took the PC back to the same issue of no output. I checked the Voltage output in all points of the 24 pin connector and it seems to be in the right range. I tried to clear BIOS, drain any excess charge, turn on without any non-essential components. Nothing worked. So I bought a new PSU the result was still the same. Opened the PC and removed the CPU and cleaned the socket. Reinserted it with new thermal compound on the fan yet nothing.

 

[PetarS1]

If there is no beep without any RAM, it is most probably the motherboard. If possible, buy another one. Though, consult on other forums also before taking my word, because i am still not confident in my knowledge.