x15 R2, 2 red 3 blue blinking code, problem

That would indicate a memory problem. Have you tried reseating the RAM and I would also suggest running diagnostics, F12 at boot, just to confirm hardware integrity.

I don't think it's the memory even tough that's what the error code means, as I have done 1 full day continues memory test returning all working properly.

I believe this is something else, something more complex that needs someone with high knowledge of laptop working to figure out. And I hope someone here has that knowledg

@San84​ Did you run Dell diagnostic or Memtest86 which is far more aggressive. 

@JOcean​ yes I have, everything returned Good.

Als i run extensieve intelburn in test no issiues what so ever.

That's why I said I doubt this has anything to do with 2red 3 blue memory error or cpu/gpu in that case. If that was the case it would shown during one of those tests and the laptop wouldn't be able to runfor more then month now without issues, like I mention when u am able to turn the laptop on I can use it and do anything with it without any issiues what so ever. All games are running super smooth even the latest gen.

I have also updated the bios to lat st version in hope this would resolve but sadly no 

Hey @San84 , I’m facing the exact same problem on my X15 R1. Were you able to find a solution? 

@Sanchit Sahdev​ 

Hey Sanchit, to be honest this is the hardest repair job I ever had in my life. 

I still haven't managed to fix it after replacing so many ICs and even the bga memory chips.

I have come to the conclusion that the issiue is not memory itself but inside the CPU . Probably a cold ball solder joint and it would need to be reflowed/reballed or a new cpu.

Or in your case the South bridge chip , as your motherboard have it separately and not in the cpu itself like mine does.

Oh wow that is a VERY critical error for our not-so-old laptops. Thanks for the insights. My laptop managed to luckily boot again; I will not be shutting it down now. Keep me posted if you're able to find the exact problem and a solution, I will as well.