Is a motherboard still safe after blowing a...fuse?

Magneu

Commendable
Feb 12, 2017
1
0
1,510
Hey there, first post on this site, decent-time lurker.

So I recently upgraded to an EVGA 1070, and needed a new PSU as I was going to dedicate my old MSI 970 to PhysX (my favorite game is intensely PhsyX heavy) and my old PSU didn't have enough juice. Motherboard is an MSI Z97 Gaming 5, RAM is 16gb of Kingston Hyper Fury X 1866mhz DDR3, CPU is an i5 4690k (was running a 4.5ghz OC at the time, but is currently 3.5ghz with additional turbo).

Got an EVGA 850 BQ PSU from Best Buy (not terribly concerned with efficiency) to replace my EVGA 500W, and that's where stuff started to go wrong.

Hooked up the new PSU correctly (friend and I triple checked connections), and the best we got was the CPU fan starting up for a second, then stopping, and refusing to do it unless I disconnected then reconnected the PSU for a minute or two. Believing the PSU was faulty, we hooked up my old PSU to test, but forgot to attach the PCI-E cable to the 1070; this is where I think I goofed. The 850 PSU was connected to the SATA drivers and nothing else (no power supplied to 850 PSU), while the 500W was connected to the motherboard and CPU, and was drawing power from the wall. Attempted to boot (not connected to monitors or any peripherals), and immediately a fuse or something right above RAM slot four immediately popped and blew some flame; in a half-second I shut down, blew it out, and freaked out.

Waited for it to cool down, then took some rubbing alcohol and a Q-tip and gently wiped it down; turns out the actual fuse (little copper metal thing) was just fine, just had soot on it; the box below it however, had a little hole in the middle and a tiny amount of an orange substance around it (pictures coming soon).

After hours of searching on my friends computer, we determined that the fuse belongs to a CPU fan control, which had nothing plugged in at the time. The only thing that possibly could have been touching the fan control was a rubber-coated cable from my CPU cooler. We entirely reconnected the old PSU at that point.

From there, we took a huge risk, and booted; everything works fine, OC on CPU has reset, computer runs great. I even loaded up a game (Warframe) on a 2560x1440 144hz monitor at highest settings, ran just fine, temperatures are all normal; only very strange thing is that MSI Afterburner has locked me out of voltage control, which may be due to the new GPU being an EVGA?

Basically, before I shell out good bucks on a new motherboard (I love my Z97 Gaming 5, and it's near 200 bucks new, and I can't find refurbished at the moment), I want to know if it is safe to use the board still. As far as I can tell, the fuse hasn't blown, but I don't know what the box is that did; it isn't a capacitor AFAIK, but I'm not sure. I'll upload pictures when I can, but if you look up MSI Z97 Gaming 5, it's the fuse directly above the RAM slot four, and the tiny black box directly below the copper fuse.

TL;DR; new PSU didn't work, plugged in old PSU to CPU/motherboard and forgot GPU, something at an unused CPU fan mount blew, fully wired old PSU up, computer runs high demand games just fine (no overclocking).