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Computer Voodoo?
jbeaupre asks: "A corollary to 'Any sufficiently advanced technology is indistinguishable from magic' is that sometimes users have to resort to what I call 'computer voodoo.' You don't know why it works, you barely care how it works, but you find yourself doing the strangest things because it just seems to work. I'm talking about things like: smacking a PC every 5 seconds for an hour to keep it from stalling on a hard drive reformat (with nary a problem after the reformat); or figuring out the only way to get a PC partially fried by lightning to recognize an ethernet card, after booting into Windows, is to start the computer by yanking the card out and shoving it back in (thereby starting the boot processes). What wacky stuff have you done that makes no obvious sense, but just works?"
For most problems, I find smacking the user is more effective than smacking the computer.
I had to code a standards compliant page with Dreamweaver ... now THAT'S voodoo
When somebody has a problem that they want me to fix, my mere presence and their attempt to repeat the problem makes it go away.
Usually whenever it would start going on the fritz a good punch or kick to the tower would get it going again. And also stop that damn whirring noise. It always makes me laugh when I'd see people hitting the monitor. Because THAT is where everything is XD
Not sure how it works, but I've saved 2 or 3 hard drives that reported tons of bad sectors with cat /dev/urandom > /dev/hdb and then cat /dev/zero > /dev/hdb and repeating that a couple times. Seems to alleviate all the problems. The drives wouldn't format, and all the data would get corrupted, but after doing that trick, they haven't had a problem (with the longest running drive being 2 years after the fix and still going).
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
I once had a hard drive that wouldn't spin up if the computer had been off a few days. The only way was turning it by 90 degrees every time before booting the computer.
In my repair monkey days, my shop used to handle data recovery jobs of all kinds. The problems ranged from minor filesystem corruption or unbootable drives to physical damage - heads, and even a bullet through a hard drive (No, I wasn't able to get anything off that one).
We had a variety of methods for dealing with the physically damaged drives that had suffered a head crash, but my boss had a technique he called the 'massage'. A clicking or noisy drive would be rotated around its various axes until the BIOS would recognize it on boot. Sometimes the clicking would stop and he would sit there holding the drive in that position or prop it up to keep it there.
Another method we used was to freeze the drives for a period of 15 minutes to 6 or 8 hours. Sometimes this allowed enough contraction to let the tracks line up again, and we'd get as much data as we could with the drive cold. Once, we even froze a drive between two ziploc bags of water with IDE and power cables hanging out the edge to keep the drive colder longer. It worked!
-- Shade
Technology tips and tricks.
I gotta stop using gentoo.
A bad analogy is like a leaky screwdriver.
-- Shade
Technology tips and tricks.
On the first pc I built one of the best ways to keep it in line in its last few weeks with me was to randomly yell and smack the pc, it didnt know when it would happen so it didnt risk crapping out on me :P
Nah, Ive never had to rely on any voodoo to keep my pc running .. but to eliminate some annoying buzzing sounds from fans nothing beats a swift smack on the top left corner of the case.
I had a roommate that smacked his pc cause it wasnt working the way he wanted it to .. but it was working perfectly fine (no hardware or software issues - all user issues) .. I told him I'd have to start a support group for his electronics (he hit everything) if he kept it up. Electronic Victims of **** still lives to this day (name censored so he doesnt come after me :P)
If it takes effort to do, let someone else do it.
real nerds dont code html by hand, they write a script to code the html for them
back in the day we didnt have no old school
However, after I installed the card, Windows 2000 would crash with the following BSOD:
Annoying as heck-- somewhat expected from a cheap network card.
So one day I was wat home downloading Fedora with bittorrent--- my DSL connection was maxxed out. There was too much interference on the line, so I hit the little 'channel' button to switch to a different channel.
As soon as I hit the button on the phone -- *boom*, the computer threw up the Blue Screen of Death. ANd sure enough, I reboot, hit the button on the phone-- and *boom* -- Computer crashes again.
I have since replaced all of the D-Link cards with cards from other manufacturers.
"Can of worms? The can is open... the worms are everywhere."
Actually, some people laugh at that, but I have the same thing happen. I remember a couple of years ago, I convinced a friend of mine to try switching from Mandrake to Suse on his laptop. Chatting with him on the phone, he complained that booting up the system was taking 15+ minutes. I drove over there to see if I could possibly diagnose the problem (he had been using linux for a while, but was never really much for sysadmining). I walk over, he boots up the machine, it boots up very quickly and runs flawlessly. Tried a couple of more times, same quick bootup. After I went home, he tried rebooting and ran into the same problem. We were both dumbfounded for quite a while, until I finally worked out that it was because when he had been using it, he was sitting in his living room, and it had hung waiting for eth0 to time out, but when I came over to look at it he put it in the docking station and plugged in the ethernet cable.
I've seen other situations like this. Many times, it's because the user is doing something they know is stupid/they shouldn't be doing, and with a techie looking over their shoulder they don't do it.
Famous Last Words: "hmm...wikipedia says it's edible"
Got to love old school hacking
I have mod points and I am not afraid to use them
Why in God's holy name does Windows fail to boot one time, and then boot successfully the second time?
Hardware problems.
Information wants to be free.
Entertainment wants to be paid.
You just want to be cheap.
Or they've been skipping some step that they figure is useless and they're sure they've done already but it didn't help. When demonstrating it for the techie they throw that step in just to save time. They're certain that when it doesn't work the techie will tell them they missed a step and make them do it all over including that step; it still wouldn't work and it would be a waste of time.
Except that the step WAS crucial, and now it works. They had some other problem, and they'd fixed it, but now by skipping that step they still get the problem.
I wish I could attribute that just to dumb users, but I've made that mistake myself. "Yes, I TRIED rebooting the router... oh, it worked this time. Never mind."
Tell the enduser their network cable "got reversed" and somebody will have to go over there and turn it around for them.
First, if you ask someone to put the phone down to check for link light, they'll answer back in 3 seconds without checking.
Second, even if they actually wouldn't lie about it, they'd never get under a desk to fix it in the first place.
Even guys in suits do it every time, if you say someone will be over "later" to reverse their (known loose) network cable.
End result -- works every time if you do it right, and no credibility lost since everybody understands what happened.
Just today I turned my computer on after leaving it on hibernate for a week. The "thaw" as I guess it could be called, failed (the computer hung before showing anything useful) so I rebooted. Windows starts up fine and then tells me my hardware has changed and I need to reactivate Windows. Except my hardware hadn't changed since the last boot (over the course of owning this computer, admittedly it had changed a lot). Oh wait, I can't activate over the Internet anymore, I've installed it too many times on the same machine, I have to call Microsoft, speak a 42 digit number slowly into the phone, get put on hold, be told I spoke the number wrong, put on hold again, read part of the number to a person, and then type another 42 digit number read to me over the phone. Then my computer will work again.
If I had mod points left I would have done it myself. I never actually thought to try and do that. It makes perfect sense now that you said it. I always assumed that when used dd setting the input file and output file to the same thing would cause it to get stuck in an infinite loop. But now that you posted that and I thought it out some more, it makes perfect sense. DD will just grab the amount of data you specified as the block size from the input file and dump it to the first part of the output file (which in this case would be the same section of the disk). It will then increment by the block size on the input file and place copy it to the output file by the same incrementation of the block size, rinse, repeat ad infinum until it hits EOF...
Again, great little one liner command to remember in the tool bag...
We were all warned a long time ago that MS products sucked, remember the Magic 8 Ball said, "Outlook not so good"
I keep various old expansion cards, motherboards, and processors hanging on the wall in plain sight of my beige box. The threat of disembowelment seems to keep it inline.
"Me fail English, that's unpossible." --Ralphie
True story: I used to identify bad RAM chips in old Apple II units with a dowsing rod. Finding one bad RAM chip out of 24 was a horrible pain in the ass, the normal procedure was to remove half of them, replace those with known-good RAM chips, see if the mem diagnostic passed, ok, it wasn't in the half I removed, put those back. Take out half of the chips that weren't removed before, replace with known good chips, repeat, etc. in a binary search pattern. This was horribly unproductive, particularly if the memory fault was intermittent. And even worse, once in a while, due to all the handling and insertion/extraction, or maybe just from static discharges, you'd ruin a chip in the known-good set, which really screwed things up, you could go back and forth for HOURS.
I remember when I was a little kid, I used to watch the old Tom Snyder Tomorrow show on late night TV, and some weird guy demonstrated how to dowse using a couple of bent wires made from coat hangers. I was skeptical, but eventually I became known for some rather startling dowsing stunts, I used to challenge people to hide my keys in a location I was unfamiliar with, in houses or buildings I'd never been to, and could find them 4 times out of 5. So when I became a computer tech, I figured, what the hell, it couldn't hurt, it couldn't possibly take MORE time to try dowsing than to do the elaborate binary search method. And to my astonishment, it was a LOT faster. Sometimes it took me a couple of tries, but pulling just a couple of individual chips was a lot faster than pulling 12 chips at a time, and my results were way above the expected average of just pulling a chip at random. BUT.. I made absolutely sure that nobody ever saw me dowsing on their machines. This is Computer SCIENCE, after all, it isn't computer VOODOO. Ha!
I used to have a Performa 5200 back when I started college, and if you're not familiar with the machine, it's arguably the worst Macintosh ever made. Ever. The only thing it excelled at was displaying grainy TV on the TV tuner card you could get for it.
Read that second link for all the gory details of why the follow scenario works, and you'll shudder.
I used to note in college that when doing particularly fast FTP transfers that saturated by 10-Base-T card that the machine would often lock up within a minute of starting the transfer. For months, I fiddled around and noticed that if I was actively working that this didn't happen. Eventually, I found the article I mentioned and realized that if I kept moving the mouse constantly, the machine wouldn't get in whatever weird state locked up the machine and I could finish my transfers. That's right -- to run FTP (or any other sustained, saturated transfer), I had to sit there moving the mouse in circles through the entire transfer.
Essentially, the "Left 32" bus described in the article was shared by the 16-bit Apple Desktop Bus (for mouse and keyboard) and the 16-bit networking card (as well as audio and the 8-bit SCSI controller). So long as I kept interrupting the bus with input from ADB, the networking card was unable to flood the controller that had to make sense of all the different bit-widths and clock speeds between the various busses hanging off of it, and the machine wouldn't lock up.
Now how's that for some serious computer voodoo?
If it's for-profit but free, you're not the customer -- you're the product (e.g., the Slashdot Beta's "audience").
Why in God's holy name does Windows fail to boot one time, and then boot successfully the second time?
Hah. I had something close to that one. A friend's Windows XP Home system. Boot it up, runs fine for about 30 seconds, then locks up hard. Reboot it, works fine for as long as you like. Next time you boot it up, locks up after about 30 seconds. Reboot, works fine. Lather, rinse, repeat.
I booted it up off a Knoppix disc and ran a bunch of hardware tests -- nothing. And no problems with locking up either.
Back to Windows -- same thing.
I eventually realized the pattern: after a clean Windows shutdown, it would lock up 30 seconds after the next boot. After a dirty shutdown (e.g. power cycle or reset button), it would boot up fine. Obviously the Windows shutdown was leaving something in a funky state for next time. Beats me what.
I told my friend she had the choice of doing a re-install and keeping fingers crossed, or always shutting it down with the power switch, or moving to Linux. I don't recall what she did beyond passing the box on to her kids because she'd already got a new one for herself.
-- Alastair
My dad works for the Arkansas Washington County Road Service, and he is something of a computer nut, so he would 'recover' the computers they were throwing out. I was pretty profoundly poor and also a computer nut, so I would take some of the stuff off his hands.
Anyway, I used to have three or four MFM hard drives in various states of disrepair. (I think they were 40 *meg* hard drives, but I only had a controller to control up to 20 meg, to give an idea how old this hardware was.) One by one they died, until finally only one was left. When it gave up the ghost, it would spin up, then immediately spin back down. I dug into it and found some connections I could short across while it was spinning up and then break the connection, and it would keep running. I was too poor to want to go spend $1 on a pushbutton, so I just had two wires hanging out of the front of the computer that I held together while booting the PC. I ran it that way for over a year...
A non-computer story, but more interesting one, is of an old Ford Escort I used to have. The starter went out on it, and, again, I was poor, so I dug into it. I finally figured out that the relay was kicking out too far and shorting out against the housing, so I duct taped a kitchen sponge to the inside of the relay housing and put it back together. I never had a problem with the starter again for the 2 years I had the car.
That same car later had the fuel pump go out. When it went out, I asked my stepdad if I should check to make sure the pump was out instead of a wiring or power problem, and he said nah, it's the pump. So I bought a replacement - it didn't help. So, I hunted around under the hood until I found some leads that were hot when the key was on, but not when it was off, and I used ties to secure an extension cord from the leads to the fuel pump. The car ran fine.
That was in the summer. When winter came along, one day I needed to defrost the front window as I was driving down the road. I flipped the vent from dash to defrost, and the engine stopped running. (I was doing 50 mph down the road at the time.) I flipped it back to vent, and the engine started right back up again.
Somehow I had found a wire that only gave power when the vent was not on defrost. I never fixed it, just kept the inside warm enough that it didn't frost over.
Now I'm a software developer and not poor. I virtually never fix (or jerry rig) anything myself, other than software and the occasional computer hardware issue.
What wacky stuff have you done that makes no obvious sense, but just works?
Ask Slashdot.
(...though I'm not quite sure it works...)
--<Mike>--
I had (still have, actually) this old Compaq Presario computer with a Pentium 200 MMX processor. The thing was never the most stable computer out there and was a pain in the but to work on, having non-standard screws and proprietay memory, as most Compaqs of that era did. One day I realized that I had a bunch of old hard drives lying around, so I decide to make this Compaq into a makeshift file server by adding the two larger drives in to the machine and brought it to school with my at the start of my Senior year. The machine's sole purpose was to act as a file server AND as a second internet/instant messaging terminal that I could use when my primary desktop was otherwise engaged. The machine didn't do this well as it seemed to suffer a 25% random reboot rate while using it. (Windows 98, couldn't even get Linux to come close to running on it.) This wasn't really any different from the sort of behavior it had shown since the day we purchased it, shortly after the MMX processors were released, so I just put up with it until...
;)
One day I'm playing Serious Sam over the LAN with some friends. There's a brief lull in the action and so I reach over for the 1 gallon bottle of apple juice I was drinking from. Well, instead of picking up the apple juice, I tip it over and the entire contents spill out ON TOP OF the Compaq. I of course, immediately jump in to disaster recovery mode and race to the kitchen to grab the paper towels. I start cleaning up the mess, expecting the wrost for the Compaq in the process. I could see where there was apple juice in all of the little crevices and I'm darn sure some of it actually got into the computer. Some had spilled on to some school papers lying next to the machine and I wanted to make sure I didn't lose any notes so I took plenty of time to salvage those papers.
After I finished cleaning up the mess, I check the computer. Mouse and keyboard input seem OK. I start up Winamp and it seems to work OK. I run scandisk on all of the drives and they all report being OK. I can't find a single thing wrong with this computer. And I'll be damned if that computer didn't have a single random reboot after I spilled apple juice on it. It became the object of admiration and jokes amongst my friends, and one friend even managed to find one of those fruity, rainbow colored Apple Computer stickers that he wanted me to put on the case. I never even bothered to open up the computer to asses the damages (partly becuase I was lazy and didn't have a torx screw driver at school). Truth be told, I was afraid to even move the comptuer or otherwise disturb it since it seemed to be working OK.
A quick addendum to this story... right before graduation I purchased another hard drive for my primary desktop machine that was about 4 times the total capacity of the drives in the apple computer. I copied all of my data off the apple computer on to this drive and pretty much relegated the apple solely to web surfing detail. About a year and a half later, I need another hard drive for a client machine and so I decide to finally open the apple computer to raid one of the hard drives in it. I was even more amazed then that the computer still worked. There was brown, sticky apple juice residue on everything in the computer. There was even a puddle of this gooey gel that had pooled at the bottom of the case. It was all over the cables, the drives, everything. I was even more surprised and even a little bit proud that the computer still worked after that ordeal.
I guess that just goes to show: if you want a stable computer, get an Apple.
If Murphy's Law can go wrong, it will.
We wrote a script once that would gradually slow down the mouse pointer. We installed it on the interns computers and watched them get frustrated when their mouse pointer wouldn't move. We explained to them that they had to unplug the mouse, swing the plug end rapidly around their heads, and then plug it back in, and it would be fixed.
We would conspiciously watch from quite a few cubes away and watch this mice get whipped around in the air! It was the most hilarous thing we've ever seen! You'd think that they wouldn't buy it, but when push came to shove they did it and it worked for them after looking like fools!
We're all hypocrites. We all have hidden parts, it's the contrast between them that make us more a hypocrite than others
Do you mean the first time or the second time?
"Not an actor, but he plays one on TV."
I knew a guy who could only log into the network while sitting down. If he was standing up when he tried to log in, no dice.
Turns out he touch typed while sitting, but had to look at the keyboard while standing - and since he "cleaned" his keyboard and put a few key tops back in the wrong places, he was mis-typing has password if he was standing up.