MacBook Pro (15' A1990) CPU overload on graphics switching

[lizzie24]

My CPU is going crazy anytime I try to connect my external monitor or play a game. The CPU also goes crazy (from under 1% to 70%) when I turn off automatic graphic switching. Here's where it all went wrong. I decided I should open up my MacBook Pro (15' A1990) and get the dust out since it had been running hot anytime I was gaming. I blew out the fans and they did look really dusty. Not a lot of dust came out though so I'm wondering if it didn't get all caught up underneath the board. But…. This is the stupid part… I was going to just pop out the fans and clean them until I realized how much time and effort I didn't have to spend disassembling the laptop. But in the process I grabbed onto a cable with my tweezers and was about to pull it out when I got a spark! I had forgot to unhook the battery. 😩 After that I was getting all kinds of issues surrounding the graphics. I did also do a system update to Sonoma yesterday but I'm fairly certain the problem was happening before that. All the components “look” ok but maybe I shorted something out?? I have a multimeter but I have no idea what the readings should be for those components.

[lizzie24]

The spark was from this section of components. Anyone know if these could affect the GPU or anything to cause graphics related issues?

[lizzie24]

My CPU is throttling anytime the GPU is engaged. I cannot use an external monitor, or start up games... just turning off the graphics switching causes that CPU to go crazy. This started after I caused a spark on the board. I thought I'd disconnected the battery (apple has weird batteries in new models) but hadn't and my tweezers momentarily connected with some componets and caused a spark. I took the laptop in to a guy who found a couple shorted out resistors. He simply removed them from the board, did not re-solder any on, and said the board seemed to be working fine. I picked up today and the problem still exists!! ugh. All that time and money. Ive been trying to learn how to read the schematics and boardviews but I just don't know enough to figure it out. does it sound like the problem is with the GPU? could the GPU itself be shorted out? how can I test that? ANY other thoughts or advice welcome! One other thing.... I installed a system update to OS Sonoma that day as well though I doubt that has anything to do with it. sounds more like a hardware issue, right?

I did run some tests and reproduced the issue when the dedicated graphics were engaged. could the GPU still work while shorted and just cause issues with the dedicated graphics? So strange!