[SOLVED] Computer has no monitor display, no keyboard and mouse lights but fans are spinning, (helping a friend)

[goofy001]

So my friend bought an SSD and installed OS in it for his old system unit, it was still working at the very least and then he decided to try his old hdd with an OS if it still works but hdd only boots in test mode so he decided to go back to SSD and then this happens.

 

[morethanjsan]

I'm the friend he's talking about. Along with that, I already tried switching sata cables but no luck. I just wanna know what might be causing the problem, is it the mobo? The hdd or ssd? Or something else? Thankyou.

 

[unrealbanana]

I had this problem before, I fixed it by resetting the motherboard BIOS settings. Here's how. Hope it helps!

 

[ubehome]

Might be worth trying to reseat everything, especially the ram and connecting cables. Something may have been knocked loose