Ok, after 8 years, I found out the problem was. The GPU was never over heating. The problem was (I even added the latest i7-2860QM CPU – about that model, I forgot). But the last time, on the GPU I pressed so hard so finally it clicked the pipe and the GPU and I could never again overheat, no matter I did, it was over max 58 celsius.
I replaced the whole Laptop and it was a very very forceful push on the GPU to have finally touching the pipes and it is now is perfect like 10 years ago… (4 cores, 3.6 GHZ turbo, 2.5 GHZ base).
So if you ever think your Laptop is overheating Dell l502x, if your forceful push the pipe into the GPU, it will be perfect as you purchased.
solved dell l502x overheating for many years