Can you estimate the model year it is? If it's anything before 2015 I wouldn't take it in for repair for several reasons:
- It is considered vintage by Apple which means replacement parts are not available and an Apple Store will not work on it.
- It has no monetary value left and will not run current versions of Mac OS and your third party apps cannot be updated. Spending money on an old computer makes no sense, if you manage to get it repaired that means you still have a computer that is vintage and has no value.
- It simply has seen it's day and it is time to be replaced.
However if it is a 27" then remove the RAM and re-seat it. By the way, did you upgrade the RAM yourself if so, what brand of RAM is installed?