Over the past six months, I've been wrangling with a random freeze hardware issue that I haven't been able to pin down. The random freezes are a bit like this: screen stays the same, audio cuts out. Occasionally I'll get an orangeish-brown screen or a grey screen. Fans and everything else still running fine, I think the disks even still spin, though with no activity. Temps are always well within safe range when it freezes.
I started out getting these crashes only occasionally (hence the six-month troubleshooting period), and generally only when playing high-bitrate video files. Now they're much more common and generally hit me whenever I try to load up any video game or video file, and occasionally when browsing the internet.
I've eliminated the following components:
Video card. Popped in an old Radeon card, issue persists.
Ram. Building a PC for a friend, so I swapped ram sticks to see what happens. No change.
HDD/Software. Booted up an install of Windows onna USB stick, still crashes.
Power Supply: Same story with Ram.
Motherboard: Again, same story. Both MBs are the same model.
At this point, I think the only thing I haven't replaced is the processor.
But see, here is when things get a little strange. Over the course of the past six months, I have noticed there was a slight correlation between the frequency of crashes and how often I air-dusted my PC. If I dust it off, immediately the condition improves (but never gets fixed completely). So, I left it alone for a few months until the crashes were so frequent opening a tab in my internet browser would cause my PC to freeze up. I then dusted each individual component until I discovered it was dusting my PSU that improved things. You would understand that I was scratching my head a bit when replacing the PSU did nothing.
So right now I'm considering replacing the processor just to see if that would fix things. At the same time, I'm a bit apprehensive, worried that the crashes would still persist and the root problem is something not even in my PC, like the wiring to my house or something like that. I can't really find any way to connect dust buildup in my PSU to my CPU failing.
You're right, that is bizarre. My first instinct, given that the symptoms included graphical anomalies, was a failed video card. My second instinct was the PSU. Given that you've swapped both of those, we'll have to get a bit more out there.
First thing I would do is run a CPU stress test like Prime95 or AIDA64. Run for at least a couple of hours. See if it crashes faster or more often than you'd expect otherwise. I suspect you'll find things run fine, because CPU trouble would be unlikely to cause those random orange/gray screens, but it's worth checking out.
Also, this is kind of a random thought, but I sense that's what you're looking for: try swapping out the case, or just running the components on a test bench. Other than the CPU, it's the only thing you haven't tried changing. There's a (probably tiny) chance that you've got some kind of short circuit happening with the front panel connectors, power switch leads, or a warped bit of metal in the case itself.
Oh, and triple-check all your connections, especially PSU cables.
Thanks for suggesting Prime95. All this time and I never considered asking someone about CPU-specific benchmark programs to test the CPU.
Immediately upon firing up the benchmark, my computer freezes up. Messing around with the settings, I turned down the number of cores and the app doesn't crash. I get maybe a 50/50 chance of it crashing on 3 cores, no crashes on 2. I get a lot of rounding errors however.
Anyway, following this train of thought, I went into my BIOS and disabled some cores and found my computer to be a lot more stable. This will probably hold me over until I have time to get a new processor. Still have no idea how this all relates to dusting my PSU though. I'll give you guys an update when I slot in a new proc.