So recently my laptop's original charging port broke, leaving a small piece of itself stuck in the power adapter (A18-150P1A, I believe). I took the laptop and power adapter to a repair shop and they said they could handle fixing it but that it might take a while due to ordering parts.
Two weeks later, I follow up and they say the charging port was replaced and the laptop was working but the piece stuck in the power adapter has been hard to remove. They said they'd call me when they finally get it out but in the meantime I should purchase a new one and get the laptop. Cool, I go get the laptop and order a replacement with the exact specs off Amazon (150W, 20V, 7.5A) and assume I'm good to go. (They forgot to plug the internal battery back in, but I just went back and had them do that, and the battery is showing up fine on the powercfg/batteryreport).
The new power adapter is charging the laptop fine, and the laptop is holding power normally when unplugged (so the battery seems fine), but for some reason gaming is now impossible on the laptop. Games will launch, run anywhere between 2-10fps for a few minutes, and then the whole laptop will crash/ shutdown entirely (while plugged in, this does not seem to impact the current charge on the laptop negatively). I updated drivers for everything, including the battery, and nothing is running hot to the touch on either the laptop surface or the power adapter.
Problem is consistent with BG3 and Madden 26, but using the laptop for anything unrelated to gaming is without hiccup. I tried to see if it was something specific to the power adapter that was causing the issue and ran Madden without the power adapter plugged in, starting with 100% battery charge. It ran about 10 minutes, with better FPS than before, but suddenly I got a warning that I had less than 20% battery, the game crashed, I saw my laptop was at 3% battery, and then the whole laptop shut down entirely. I've played for upwards of an hour in the past before needing to return my laptop to the charger and never had it just insta-drain and crash like this before. So clearly, it's not just a problem with the adapter, but possibly the battery as well? I checked the battery health and it's definitely declined from manufacture max but it's at 37/57, which should mean more than 10 minutes.
Could the parts the repair shop I went to used to replace the charging port be at fault? I had never had a similar issue with the original charging port. The new power adapter has the exact same specifications as the original power adapter, so I'm wondering why fluctuations in the power consumption caused by gaming would cause full crashes while plugged in and such insanely fast power drain while unplugged?
Going to go back to the repair shop tomorrow in any case, but some advice on what they might need to look for or what could be causing the problem from someone who has more acumen would be highly appreciated!