BSOD after several days of Firefox issues

I've detailed problems I've had since Windows Update ran important updates on the 15th here-

Firefox issues- sudden total PC freezing

But in summary-

1) night of the 16th, Firefox freezes, PC won't respond, I have to unplug and do a forced manual restart.
2) I disabled several plugins. Right after the PC gets a bit jittery, I figure Firefox is doing stuff in the background as it lasts a couple of minutes
3) night of the 19th I get the same freeze with Firefox upon starting the browser. Was almost around the same time of night as the freeze on the 16th
4) morning of the 20th, about 5:30 AM the PC freezes again, Firefox is NOT running, but it lasts maybe 30 seconds. Event viewer suggests the video driver was failing to respond
5) about 6:45 it does this again, only to BSOD and restart, but sits on a black screen
6) hit power button to shut down, restart, Windows sits at the black logo screen and doesn't load
7) shut down manually, open case, replace SATA cable to hard drive, restart
8) System tools run because Windows didn't boot, startup repair runs. Diagnostic shows no specific fault found, only a generic issue. This runs and PC reboots to a previous good state, and I haven't had any issues since.

I'm set to record BSOD info but I cannot find the dump file, I think Windows failure to restart failed to create the dump. I also think the manual restarts failed to log other issues. I did not see the screen long enough before reboot to recall what it said.

I'm trying to determine the cause of all this. Faulty video card driver? Unfortunately I seem to be at the most recent driver for this integrated chip. The WU on the 15th causing issues? Maybe, it's the only change since. Bad hardware? WD's HDD utility, sfc /scannow and Chkdsk say the hard drive is fine, though that SATA cable was old and bent at a good angle in the case so maybe...

Likewise, it's possible the update goofed with Firefox or its plugins, but the 2 forced power downs and reboots could've caused issues. The fact both Firefox freezes occurred around the same time at night also seems strange- conflict with a running windows process scheduled for around then?

I want to figure out what happened, to hopefully make sure these issues are done. I've 99% ruled out malware after scans with several programs. If this is a Windows issue I do have my Gateway system restore and install discs(it's not a Windows 7 retail disc, it's W7 restore for this specific model PC) and could either reinstall Windows, or if the HDD perhaps is going bad, could pop a new one in(bought a spare in January and kept it in storage unused)

A follow-up-

Windows said my video drivers were up to date, but after updating Java to current, removing two old Java installs, and getting Intel's download center utility to run, THAT found a video driver update, which I've now installed. I've restarted fine, nothing of my desktop is changed and I just ran GZDoom to test gaming and it ran same as before so...

I know the video driver was having an issue from logs in event viewer. However, I also want to rule out other issues such as a bad Windows Update causing conflicts or any hardware failure, given this problem only started after the WU on the 15th, and I want to rule out any issues possibly being the result of forced shutdowns(partly as I live in an area prone for brief blackouts during storms and other causes- squirrel got fried one day and knocked power out, someone hit a pole a few months back... I got a HDD baked in 2012 by such an outage/surge). If I may need new hardware, or to pop my second HDD in i want to diagnose this before my PC could potentially shut down leaving me with no net access or info resources.

Further note- I bought a new DVD-RW drive in January, an Asus, as the factory OEM one include with the PC had always been unreliable junk. The new one works better but I left the old one in anyway as it still works. I had no conflicts with both drives installed but... could this have also caused any issues? It's actually not installed ATM, as I needed to swap SATA cables and replace the one I'd been using for the HDD(I'll probably buy 2 fresh cables this week).