So it first started last night. PC completely restarted itself. No really big deal, check memory and see if anything is corrupt and it's not. Get on again and try to play GTA, I get an error after taking 5 steps. The error was "your PC is low on memory." OK. Not cool, but maybe it's the GPU needing to be reset as it has been moved from uni to home several times since I bought the GPU and I never reset it. Take case off and reset GPU and pull RAM too because it's involved too. So I thought, I'm on now after resetting the RAM and GPU and I load up GTA hoping it's fixed and it goes good for about a mile. GTA freezes. I sit there for about 3 minutes and steam closes on my other screen, then GTA crashes. Open up task manager and 100% disk is used my windows installer modules (whatever it is. Can't remember currently) I Google it to see why it's using so much disk and find out Windows Update is currently taking place. Really wanted to try GTA one last time. So I do. I get to the loading screen and my primary monitor loses output and GTA music is still playing. My secondary monitor goes blank but doesn't turn off, basically acts like the GPU is trying to switch displays. Nothing happens for 10 minutes and I'm forced to shut down by holding down the power button. PC is extremely slow on boot up and I have no funds to replace. What can/should I do to get by for now until August when I start getting paid. No bills or payments to worry about just no cash flow right now. Is my PC presumably dead? On its last leg? Or do I just need a clean install of Windows? My mind is thinking of everything and being an amateur at this I'm assuming it's all wrong thinking. Please help. I don't wanna be gameless for the next month and a half.

Update: after trying GTA today because Windows updates failed, I got on and it immediately said low memory. Booted in safe mode and slowly put it into full screen and 1080p runs fine and dandy for a little bit. Then it crashes again with the low memory error. Any other opinions?

Update 2: Found and fixed the issue, I had adjusted RAM usage not to long ago in Windows and the maximum was very low, bumped that up and it runs fine now. Thanks everyone for all the tips and ideas! I will be upgrading when I get the money.