Working dell 6990M in clevo (no beeping)

[ivm]

Hi.
Many of us are discontent that we can't freely swap dell and clevo AMD cards (7970m  and new rx480 included) but it seems that I may have found some clue to this problem.
Few years ago I bought a broken p170em with some ugly black 6990m. It looked like it was baked in the oven with some cookies.
I put it in my p150em and it was working normally with all sensors, data, etc. No beeping, no turning off.
What I noticed was that the other soic8 chip "2" (apl-something) was swapped as well as the main bios chip "1".
No other components were swapped and, as you know, if you just flash the main chip it won't save you from beeping.
Unfortunately I sold this card as it wasn't powerful enough for me, but now I've ordered a rx480 that I can currently use only in my gt70 and  I think it gives me some clues how to put this thing into a clevo laptop.
Does anyone have any Idea what that APL-somehing chip is and does it have its own firmware?

Edited June 27, 2018 by ivm

[TheSin]

I don't know if it will be useful to anyone, however the secret of working Dell cards is very easy - another SMBus thermal monitor chip. It's a 8-pin IC located on the bottom side of the card near one of the holes for GPU radiator on the photos from the 1st post. Clevo's cards use monitors with SMBus address 0x4D, but Dell's cards use monitors with address 0x4C, that's why P150EM can't get temperature of Dell card and starts beeping. So, to get a working Dell card in Clevo you just need to replace thermal monitor IC... or patch SMBus address in EC firmware. I guess this IC was also replaced on the topicstarter's card because area near this IC looks slightly "baked" - probably, after overheating when soldering.