[SOLVED] Freeze during boot / no POST

[tmarkk]

I have a bizarre problem, my PC runs just fine, but problems occur when booting or waking up.
Say, it's pretty much 50/50 whether the system will boot normally, or will it power up but not even POST.
Similar issue when waking up from sleep mode, but less frequently. Maybe 20% of the time the computer powers up, but without video output at all. USB seems to have no output either, since backlit keyboard or mouse doesn't light up either.
It's quite a budget build from second-hand parts though.

System setup:
Motherboard: Asus Z97-AR
CPU: Intel i5 4690K
GPU: Asus ROG strix GTX 1060 6GB
RAM: 4x4GB DDR3 1600 MHz
Primary hard drive: Crucial 480 GB SSD
Secondary drives: Kingston 120 GB SSD, Samsung 500 GB HDD
OS: Windows 10 Pro 64 bit

Worth mentioning that these issues started after being somewhat forced to 'up'grade to Windows 10.

Personally I'm assuming and hoping that the stone age era HDD is finally giving up. I recently had to discard another HDD since it became so slow that seemingly POST would take approximately forever. So slow that it caused CSGO to f'ing buffer mid-game.
Symptoms are similar this time too, the drive is significantly slower than the SSD's, however that might be me just getting used to SSD speeds. Also that would be valid reason to fill up the M.2 slot I recently discovered.
Haven't found much tips about this kind of issues, pretty much just to disable fast boot and update BIOS.

 

[Vyrvelata]

Since you had the advice about the bios do you have the latest one?
It could be 4 things.
BIOS
HDD (Try disconnecting HDD and see if the problem is there... old disk sometimes get buggy and mess up POST and the bios)
PSU
Motherboard (Leaking capacitors).

 

[tmarkk]

Checked the BIOS and there indeed was a newer version. Updated it, and boot issue didn't occur during the few restarts that the process did. Was it really that simple, time will tell.

Edit: It's been almost a week now, and there has been no more issues.