M15x random color screen

[endray]

Hey guys,

I recently upgraded my M15x with a i7 920XM and a GTX 780M.
Flashed the modified vbios, got a 330W brick, pulled the pin, installed newest drivers and did some gaming.
Everything worked pretty well, only sometimes the 780M reached 93C and clocked down, but still ran stable, never crashed.
Therefore I decided to get a finer TIM and repaste. Bought the Noctua NT-H1, carefully repasted and voila, temps dropped around 15C.
But here comes the catch: when trying Furmark or some very intensive game, the GPU reaches 88C and screen immediately turns a random color. No downclocking, no limiting, just a sudden crash. Only thing I can do is a hard reset. This doesnt happen on any other occasion, can game on 80C for an hour.

Do you guys have any sort of idea why the laptop crashes at 88C, while before it worked at 90+ without a problem?

Things I tried:
Used DDU and reinstalled the drivers, also tried older version.

CMOS reset.
Cleaned everything, no dust left anywhere.
Carefully checked the GPU for any visible damage or old TIM residue.
Tried undervolting and underclocking, only took longer to get to 88C and still crashed.

For the sake of it I actually strapped a Corsair H45 AIO to the GPU heatsink. Now i get to max 55C with furmark, but the laptop still cashes after around 2 minutes.

 

I would be happy for any suggestion, thanks!

[jexu]

Hello everyone, forgive the translation. I know I answer late, I still hope it works.

The 780m gpu is very heavy with its 100w for the M15x, it has a very high consumption and the cpu 920xm does not help. Between the 2 there is a large amount of thermal energy.

In this case, you can try to lower the micro by a 7x0qm or 8x0qm (x replace by 2 or 4). If you have one of these 45w chip on hand, something might improve. I would try it.

The most powerful configuration known these days and that is proven excellently is with 920xm and GTX970m. It is a perfect harmony. But it's still an expensive card. If someone wants to invest in a card and reliability, I recommend that configuration.

Greetings and thanks for reading.