Anatomy of a hang

[Undertoad]

I didn't need those particular files, so I just deleted them by deleting their parent directory from an explorer window. It could have just been coincidence that the hang happened when "revisiting" those particular files.

Even now, if this fixes the problem, it's hard to figure out what really happened (and not worth the time to diagnose more completely). It was probably the drive failing, but still, Windows should fail more gracefully when faced with a resource that's having trouble. It surprised me when the system hung even when I took virtual memory duties away from that drive. I could see a failing drive causing an OS a headache when it's swapping to it, but when doing more "routine" I/O, just reading files or folders, it shouldn't just lose its place that badly.

Maybe the drive was failing harder and drawing too much power in spikes, and thus causing other hardware problems?

[busterb]

Tester cannot test for all that a meter does. A best power supply test is when fully under load - in the system. A power supply disconnected cannot be properly tested. Also note voltages - the numbers. Numbers are not the published ATX limits. I asked for numbers - not the subjective "power supply is good" - for this reason.

Tw. Belive it or not but I went to electronic school years ago. And have maybe more meters laying around than most folks. Meters lie. How many people think even know how to calibrate there meter? Are you telling me that the tester doesn't simulate a load? Well maybe not, but my son said was bad. I said no because I've taken readings w/voa meter. Anyhow a new PS fixed it.

[tw]

Originally Posted by busterb

Tw. Belive it or not but I went to electronic school years ago. And have maybe more meters laying around than most folks. Meters lie. How many people think even know how to calibrate there meter? Are you telling me that the tester doesn't simulate a load? Well maybe not, but my son said was bad. I said no because I've taken readings w/voa meter. Anyhow a new PS fixed it.

If a tester provided a significant load, then tester would be too hot to handle with comfort. It would be a 300 watt hot plate. Testers apply minimal load to meet startup requirements for power supplies (some - not all - supplies need a minimal load to operate).

Yes, meters do not necessarily report RMS voltage: they lie. But that is what makes many meters so good at identifying bad power supplies. Again, note numbers provided because of how meters typically work.

I am more than just a tech. We designed power supplies even in the 1970s. Have even demonstrated on a system that was intermittent - the supply was not providing power as claimed. System would boot and mostly work. And then we put a meter on it. Quite obvious that a clone power supply could not service the load - even though the owner insisted supply was replaced and now working. Meter demonstrated otherwise. Been doing this stuff for too many decades. I prefer an oscilloscope because it says faster what I want to learn. But the meter is how field problems are identified or eliminated quickly as a suspect.

A $15 tester, among other things, does not provide a sufficient load for testing. It can declare a power supply bad but it cannot declare a power supply as good.

BTW, one final point. Notice that tester did not get hot and did not contain fans. Fans would be required if tester sufficiently loaded a power supply. Just another reason why power supply is best tested (and tested faster) still inside the computer. Just another example of why 'learning why' makes those meters a so superior solution.

BTW, do you still have a VTVM? I have a wee bit of knowledge and experience.

[tw]

Originally Posted by Undertoad

Maybe the drive was failing harder and drawing too much power in spikes, and thus causing other hardware problems?

Disk drives draw so little power as to be totally irrelevant. To cause power problems, drive would draw on the order of 100 watts - become so hot as to burn parts.

Disk drive computer talks to motherboard computer using a fixed set of command - similar to how networking works. There is nothing electrical in a disk drive that would hang a computer. Except when a computer is not so resilient - booting. Have never seen a disk drive hang any NT system except during boot. During simplistic boot programs, the software may sit waiting for a response forever - a hang. Have seen tasks hang due to a disk drive problem. Have seen NT slow to a crawl due to a bad disk. But never had an NT system lock up so that Task Manager would not operate - except when Task Manager could not load from that drive.

Marginal conditions can occur on disk hardware causing a drive's computer to not respond or reply to commands. It is why software designed to test hardware (ie from IBM) is so much better at testing disk hardware; rather than software designed to test Windows interface to hardware (Microsoft).

This being only background information - when that next drive fails. Meanwhile a drive failure should have been recorded in Microsoft's event (system) log. Find it using HELP. Also the drive hardware (an IBM creation) would have data to indicate ongoing failures. Forgot what they call that function - smart something. Just another reason why IBM hardware test software could have been more useful - I believe it is now a Toshiba product.