hey all. please read full post if you can.
i've recently noticed in my (incredibly) budget build, periodically (as in probably one every week to two weeks) i've been playing something mildly intensive for my system, usually fortnite, will run just fine for about a half an hour, then, almost randomly, will totally cut video instantly, then a few seconds later my computer will shut off. it's not an instantaneous shutoff like if you were to unplug the power cable or trip the power switch on the back of the PSU, but more like something overheating. thing is, i've been monitoring my GPU temps and rarely do they get over about 83 degrees celsius, which i know is a little toasty but shouldn't be triggering a thermal protection. i just recased my computer from a crappy montech x1 (technically the inland version) with molex fans to a fractal pop air. i was thinking maybe poor airflow or the cheap molex fans in my montech could be the culprit but this machine has pwm fans and half-decent airflow (which albeit are daisy chained but still) and it just happened again last night.
curiously, it doesn't seem to be related to how long i play, or how hot things are. it happens the same way any time that it does. screen cuts, then maybe 3-5 seconds later, machine shuts down. no error on startup. sometimes i'll run several solos matches on fortnite in a row with no problems at all, then boot up something like quake champions and play a couple matches on high graphics settings and have no issues, even running the AMD adrenalin stress test doesn't seem to trigger it. other times i'll play two games of fortnite and it'll shit out.
i just put in a new cpu cooler a couple days ago, thinking maybe it was some sort of cpu overheat from my stock cooler, didn't help. ran memtest86 today, nothing. checked crystaldiskinfo, nothing.
power supply is an ASUS tuf gaming 750w modular, which is only two years old and has given me no trouble to speak of (yet). it's a pretty decent unit as far as i can tell, not the best but it's certainly no slouch. my graphics card, however, is an rx 580 4gb which i bought used. i did realize today that i had some conflicting drivers from a previous nvidia card i had, so i wiped everything and reinstalled my amd drivers. no problems yet but as i said it's never very consistent. i am wondering if maybe it's possible for my graphics card/driver to be the culprit considering it isn't an instant shutdown but rather a black screen and then a power down. i usually up until recently would leave this machine on in my room while letting the screen go dark. not the smartest decision but i don't think it would really do a number on things.
i don't believe i've updated my bios since i got this board. i was curious if this could be the problem as well. trying to be as thorough as possible. whenever i boot up event viewer after these crashes i usually get a 6008 error and nothing really informing around it.
spec sheet (don't judge my parts list lol, i'm a musician and computing is but a hobby for me, not something i tend to dump much money into):
board: ASUS gryphon z87
processor: intel i7-4770
cpu cooler: thermalright assassin x 120r
gpu: sapphire pulse rx 580 4gb
ram: 4x 4gb DDR3 sticks, two are samsung from a dell machine i had, two are patriot from a project pc
storage: inland platinum 1tb SSD
power supply: asus tuf gold 750w modular
case: fractal pop air