Get some canned air.
Take the back off the machine and give the innards a good cleaning.
Get the vents nice and clean.
About computer: Mid 2012 MacBook Pro, 13 inch non Retina display.
Problem:
A couple of months ago my trackpad was acting up (involuntary zooming in and out, scrolling on its own). I took it to a computer repair shop and they advised it was not a trackpad issue or a battery issue (I thought the batt may have expanded due to heat or overuse, but that was not the issue apparently). The guy suggested to upgrade the RAM and said my computer was very slow and it could cause other problems.
I didn’t replace the RAM at the time and just used a mouse instead of the trackpad for a few months. Then this week, my computer screen suddenly displayed pixalated blue/gray images, shut down on its own and started beeping three times, stopped for a second then continued to beep three times etc.
I googled this issue, and again the RAM upgrade was mentioned. So I purchased new RAM cards today. The computer came with two 2GB RAM cards and I replaced these with two 4GB at 1333 MgHz.
This worked wonders for my computer’s speed, but within 30 mins the screen turned that pixelated blue colour, shut off and the beeping occurred again.
SO frustrated. Anyone know or have any insights into what’s going on?? Thank you so much!!!

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