Emergency build- no longer starting

[Pandamonium]

My HDD has been developing a bunch of bad sectors, so I backed everything up. I decided to try a low level format; while it was formatting, my computer just turned off. There was no warning whatsoever. It wouldn't start again after I discharged my PSU. Right now I can't get it to do anything. I assume that if I fried something, I would have 1) smelled it or 2) the LEDs would still turn on.

What could be wrong here? I'd like to salvage what I can of this computer...

 

[JustaGeek]

Your Hard Drive is toast.

Get a new one.

 

[Pandamonium]

The new one is en route, and I've got my data backed up. So I thought I had nothing to lose.

New symptoms: the machine will turn on after I leave it unplugged for 10mins or so. Then it turns itself off again after 15mins of uptime or so. I'm going to check to see if my HSF is making good contact, but could it be anything else? It'd kind of suck if more than my HDD died in the last week.

Edit: That's 15mins of uptime with me trying to reinstall XP on an old HDD I had laying around.

Edit2: I've got 2 Y-molex power cables splitting the power to feed 1) GPU, 2) SATA, 3) IDE. The GPU shouldn't be doing much in a dos-ish environment, and I figured the HDD power draw would max out at startup and taper off afterwards. I guess I could be straining my PSU, but it's 350W and my system runs waay less than that. (My old PSU was a Seasonic 300W).

Edit3: I've also learned that letting it stay off but "powered" (PSU connected to outlet) for 3hrs is not enough time for it to recover. But letting it stay off unpowered for ~10mins or so is sufficient to get it going again. I suppose it's likely that my PSU isn't doing too well, but I kind of don't want to believe that a 2mo old PSU would die on me.

Edit4: I just remembered that I was in a rush putting in the second Y-molex adapter. (I needed it so that I could power both the SATA and IDE drives simultaneously.) All I had was a Y adapter that I had modded to split into 5v and 7v lines (for fan speed), so I pulled out the leads and put them back into the standard 12V configuration. What I didn't do was "reset" the clips so that the connectors would stay in place. Instead, I connected the wires and pushed the ends together if they came out the back. I've since removed the second Y adapter and am now attempting a reinstall while I finish fixing the Y-adapter. I also disconnected my SATA drive from power, so my PSU load *should* be the similar to what it was before I had these shutdowns.

 

[Pandamonium]

Okay I've edited enough to feel like I justify a bump here. Plus this new development is kind of unexpected.

The system with basically a swapped HDD is still shutting down spontaneously. I'm thinking that my PSU died as well, but the odds of two hardware failures in the last week are kind of low. What do you guys think?

 

[dfuze]

I would say you have a bad power supply, that is where your symptoms point to.

I'm not sure of your system specs, but it could have also been underpowered for the components you may be running.

 

[Pandamonium]

I suppose that's possible. I just tried testing it after giving it a whole night to cool off, and it shut down again. This time, I had my case open and I was able to poke around. I touched my HSF out of curiosity, and that thing was super hot. Like, I didn't want my finger on it for more than a fraction of a second hot. I'm now wondering if it's just my mobo exercising thermal shutdown on me.

 

[jjmIII]

I'm now wondering if it's just my mobo exercising thermal shutdown on me.

That was my guess. Is the fan hard to spin (when shut down)??

 

[Pandamonium]

Nope. My machine is generally underclocked and undervolted. (I use NF7vcore/8rdavcore from hasw.net to change the multiplier/voltage on the fly in software). It's set to go from 1.1GHz/1.35V to 1.83GHz/1.35V depending on load, but most of the time it's at 1.1GHz. Since I'm undervolting by .3V, I got by with a 80mm fan set to ~7V on my heatsink. I told BIOS to use normal voltages because my motherboard was complaining about my CPU being changed, and the symptoms started occurring. Now that I've returned to my undervolted settings and cranked the fan up, I've been stable. My harddrive has been inspecting itself for the past 36hrs or so, and it's still at ~8%. I'd really like to salvage my outlook PST (I got about 60-70% of it manually), so I might let it run for up to a week or so. Anyway, it appears to be working again, I just can't really use the machine.