Freezing/Crashing after quitting out of game, and problems

[Aidenz]

My computer's been acting up recently, one day I got home, PC was turned on, but monitor wasn't, so I turned it on, moved mouse so the display would respond as usual, but it never did, the monitor said "No signal", no matter how I interacted with the PC, and apparently the lights in my keyboard (Caps Lock and Num Lock) didn't light up, as if it wasn't connected to anything; I had to hard-reset, and the PC booted up as normal.

This has happened at least twice, one time when I turned on the monitor, the desktop was all screwed up, and it didn't respond at all, totally frozen, like if someone had opened several programs at once and moved them around frenetically, causing the PC to freeze.

This has worried me, so I have already defragmented my HDD, as I suspected it might be dying, and did a chkdsk, which apparently came out with nothing out of the ordinary, but I'm not sure how to check, and it didn't seem to help, my PC is worse than ever, stuttering at opening a folder or program, and being generally not reliable and slow.

Today, following someone's advice, I attempted to reinstall my graphic drivers, but in doing so, first, the Nvidia installer "failed" installing the Graphics drivers, turning the monitor in 1280x800 resolution, and prompting the Windows Driver Installation. I cancelled it, restarted and tried installing the nvidia drivers again, which apparently succeeded, but restarting, after windows shut down, my monitor went "No signal", after a few seconds, a scrambled blue screen appeared, but disappeared a few seconds later, and the PC booted the "After an unexpected crash, do you want to boot in Safe mode?", I decided to boot it as normal, but only after the windows logo appeared on-screen, the monitor lost the signal again, which had me really worried, and after waiting several seconds, to my relief, the blue "Windows is starting" screen appeared, and proceeded to loading the desktop and everything, albeit slowly.

I feel like this is getting worse by the day, and this is really out of my understanding, and I'm actually scared of doing anything with my computer, it feels so fragile right now. I've considered reinstalling windows, but I'm not actually doing for a few days/weeks, as I need to use it every day.

Anybody has any ideas? Thanks in advance

New symptom in my latest update post:

 

[OS64]

If possible, I would remove the hard drive from your computer and put it into another computer. Boot to the regular drive on that computer and run a scan with the anti-virus of your choice as well as MalwareBytes. I would also check to make sure the graphics card is fully seated in the slot, though that is something of a long shot. Try these suggestions, keep me posted and we'll go from there. Good luck!

 

[Aidenz]

Thanks for the response! Though, it's going to be a little hard to move my hard drive, and I don't have another computer to plug it to, except for the laptop I'm using at the moment, so since I'm nervous of tinkering with hardware, I'd prefer to avoid doing hardware stuff unless it's absolutely necessary and safe
If it's of any use, I already ran a complete AV scan with Microsoft Security Essentials and MalwareBytes in Safe Mode, so I'm going to be reinstalling windows and see if it gets better, if it doesn't, I'll try and do your suggestion if you don't have any more

 

[OS64]

No problem! If you can get one, I'd highly reccommend a sata-to-usb converter, as it makes moving hard drives around for utility purposes painless. To pinpoint if the graphics card is the issue, try removing the card and running with onboard video for a bit to see if that solves the problem? If you're running windows 7, there is a handy utility to check if the system files are all intact (different from chkdsk), google System File Checker, which you can run from the command line.

 

[Aidenz]

So, after reinstalling Windows, I was browsing in Chrome, with a stream running in the background, when suddenly the PC froze, and the audio glitched, as if it had a BSOD, though the desktop looked normal, just frozen; after a few seconds of suspense, as I decided to do a hard reset, it suddenly unfroze and continued as normal.

Does this indicate what the problem is? It just seems too random

Edit: Another symptom is I was doing some stuff with windows control panel and such, and it suddenly freezes for a few seconds, then the pointer starts behaving weirdly, it changes into the "edit text" pointer, and I can barely see it, then if I hover over something clickable, it turns into the hand, but no matter where I hover at, it stays as the hand. This repeats mostly when I have the Chrome window open, so it's really confusing.
This is starting to worry me, since this affects every-day usage of windows, and I don't want to go to a technician or something to "get it repaired".

 

[Aidenz]

Update: My PC was starting to act normal, was able to boot normally (faster even), and the stuttering isn't as annoying, though when I booted up a game today, it showed a black screen, so I Alt+Tab'ed, nothing happened, then I pressed Ctrl+Alt+Delete, but the menu actually showed up really slowly, and the pointer disappeared, so I struggled to quit the game, because the computer was acting really slow, and I couldn't do anything, so I closed it using the Task Manager, but the pointer never showed up, so I decided to shut it down.

An interesting thing, right when the computer usually shuts down, only the monitor disconnected, the computer itself kept running and making noise, then after 5 seconds, it finally shut down.

Does this indicate a Memory issue or a Video Card issue?