Pc works horizontal not vertically

[dblyler]

Hello, my ThinkCentre tower works perfectly in the horizontal position - I just installed an SSD drive so I've had the cover off and had it on its side, now when I put it back in the vertical position it will not power on, I've checked all power connections i can find

 

[roblaw42]

Make sure everything is tightened down. Something seems to be lose and moving when you change the orientation of the case.

 

[jsmakkar]

Some loose connection sounds to be the reason for PC not working in vertical postion.