issue turning on

The card is showing no display and fans aren't running I'm thinking should I buy it to try and fix it or not and if so what possible fixes are there?

Hi, I have just cleaned my PC, and after that, it wouldn’t tuen on at all. Then, i discovered a loose cable which is reconnected. However, even after this, the computer only turns on for about 10 seconds, then off again, then on etc. I have tried resetting my CMOS to no avail, and removed/ moved...