I thought I'd document this for anyone with similar problems to read, hopefully you'll solve it with the least amount of hassle. Use your browser's search function to check if I covered a specific problem, or scroll down to jump straight to possible solutions.
UPDATE: Andre from Germany has a suggestion that would hopefully stretch out the lifespan of your motherboard for a little longer. Read it in the comments below.
The length does not even begin to illustrate how much time was spent trying to fix the computer by myself.
The main issue here is that Windows won't boot normally but can boot in safe mode.
If you can do this, it's probably a good idea to save any files you want to keep. You never know when it may fail.
There are all sorts of things you can do yourself, assuming you are not a complete tech idiot. You can do a Hard Disk Self Test (F12 for HPs), Memory Diagnostics (F12 in certain models, but you can also run it from System Repair), CHKDSK (run from System Repair or cmd), etc.
Here are the instructions for an HDD self test, taken from my communication with HP Techs:
Step 1. Perform a Hard Disk self test and Memory Self test in BIOS.
• Power on the system and keep tapping the F10 button when the HP Logo screen comes at startup.
• It will redirect to BIOS setup.
• click on Diagnostic Tab and select the HDD self Test.
• Once the hard Disk test is completed perform a Memory Self Test(optional in some unit).
Always perform a thorough test. It should take approximately 60-90 minutes. If the test fails then get back to us with error code. No need to perform the 2nd Step.
Step 2. If the test pass, boot the unit is safe mode, and Click on Start> Search> type 'msconfig' ( without quotation mark). Under General Tab > Start up Selection> select 'Selective Startup'. Remove the Tick Mark from 'Load Startup items', click on Okay and restart the unit. Then check if the issue persist.
However, if the issue still persist, you need to fix the issue from Service Center.
After all that, I decided to reformat, which sort of made things worse. Probably because I discovered more problems. I was pretty much going to throw myself out a window, at this point.
Reformatting kept failing and pressing F8 only gave me "Bootmgr is missing". So I did some digging.
With the recovery manager failing when I reformatted my computer (with a recovery disc, not the HP_RECOVERY partition), my own research suggested a pre-existing fault in the HP Recovery Drive. Basically, when you create a recovery disc, you burn that fault onto the disc.
There are two parts to the reformatting process - reformatting and reinstalling. This fault appeared as "Error 1002" in the second part. What it meant for me was, my computer successfully reformatted, but failed to "reinstall original content". I still couldn't load Windows in normal mode. But when I load in safe mode (F8), the recovery manager runs, and it fails again when reinstalling original content, then tries to restart itself, and obviously, fails AGAIN. It's a perpetual cycle.
That's if you're from the US and Canada. If you're from Malaysia or Australia, good luck, you're on your own. For other countries, check the link.
Alternately, you could scout around for an HP recovery disc from online stores. However, they go for about USD $100 and above.
After a whole weekend of trying to fix this myself, I gave up and sent this to the professionals.
Mr IT Dude explained, the video card was detached from the heatsink (due to extreme heat I think I heard?). The heat generated could've damaged the chip.
True enough, when the problem occured, it was sweltering.
He suggested that I change the motherboard (mobo). He also said that they've received a few of the same models with similar problems, that there's a known fault with HP Pavilion DV6000 motherboards.
So now, I'm sourcing for a replacement mobo. It's a hit or miss with this one because I could buy a lemon (from eBay), or a part that is from the faulty batch or fails for some other reason. But the Gods must really hate me for that to happen.
Or, I could just get a new laptop. But I'm unwilling to put in too much time and effort in looking for one. I have insanely long reading materials this semester.