Question Computer won't boot after cleaning

[JED1970]

This really has me baffled! All I did was remove the GPU and blow the dust out of it and my case/fans like I always have for 34 years. Except this time and it's a first the computer wouldn't do nothing! It's like it has no power.
Here's everything I've double and triple checked and tried so far.
Tried a different PSU and like 5 diffrent power cables. Tried leaving the GPU out and just using internal graphics.
All cables, MB24 pin; cpu 8 pin; GPU 16 pin; hard drive power/data cables; fans; and all other MB cables are intact and secure. And the little switch on the back of the psu was in the on position. Any ideas why it's not getting any power? I'm at a total loss on this one.

 

[punkncat]

In a situation like this is may be worthwhile to use a meter or buy one of the inexpensive testers to see if the power supplies do indeed give proper readings. If these are modular one would hope that you used the proper cables during the troubleshooting phase. Aside from that you would need to test hardware individually on or with known working parts which can be difficult for a lot of PC users. The last option would be to take it to a professional or advertising enthusiast to have it checked.

With that last suggestion comes the value/cost aspect. Is this system of a cost point that makes sense to pay what you may for a new low end build to have a pro check it? Aside from there possibly being things on there you wished to keep, as that is a backup issue on its own.