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Electronics => Projects, Designs, and Technical Stuff => Topic started by: itdontgo on August 27, 2014, 03:51:35 pm

Title: Dumpster PCs
Post by: itdontgo on August 27, 2014, 03:51:35 pm
Hi,

What software does Dave use to test his dumpster PCs.  I've got one on the office which doesn't work and before I chuck it it would be nice to know what bit it is.

Ta
Title: Re: Dumpster PCs
Post by: StubbornGreek on August 27, 2014, 04:00:40 pm
Hi,

What software does Dave use to test his dumpster PCs.  I've got one on the office which doesn't work and before I chuck it it would be nice to know what bit it is.

Ta

Why software? Does the pc boot to windows?

EDIT: If its a matter of windows still boots but you need a password, try Trinity Rescue Kit (burn iso and boot from it). However, older pc's tend to be a mess (registry, etc.). A fresh install is usually what's needed.

If no power, then look at the psu. Not sure where to take this for you without more information.
Title: Re: Dumpster PCs
Post by: edavid on August 27, 2014, 04:54:36 pm
I have no idea what Dave uses.  There are some bootable diagnostic disks like "PC Check" that are OK, but I don't know of a free one.  Otherwise you can start by running (bootable) memtest, then boot a LiveXP or Win7 PE or Linux CD (possibly from a USB stick) and run your favorite diagnostics from there.
Title: Re: Dumpster PCs
Post by: PA0PBZ on August 27, 2014, 05:10:42 pm
There's not a lot of software you can run on a pc that 'doesn't work', so please be more specific.
Title: Re: Dumpster PCs
Post by: jlmoon on August 27, 2014, 05:28:56 pm
I have no idea what Dave uses.  There are some bootable diagnostic disks like "PC Check" that are OK, but I don't know of a free one.  Otherwise you can start by running (bootable) memtest, then boot a LiveXP or Win7 PE or Linux CD (possibly from a USB stick) and run your favorite diagnostics from there.

Not that I go dumpster diving very often, but... I suspect alot of dumpster bound PC's might be of the age that the bios doesn't even support a boot option for the USB ports. 
Title: Re: Dumpster PCs
Post by: kingofkya on August 27, 2014, 05:36:35 pm
I have no idea what Dave uses.  There are some bootable diagnostic disks like "PC Check" that are OK, but I don't know of a free one.  Otherwise you can start by running (bootable) memtest, then boot a LiveXP or Win7 PE or Linux CD (possibly from a USB stick) and run your favorite diagnostics from there.

Not that I go dumpster diving very often, but... I suspect alot of dumpster bound PC's might be of the age that the bios doesn't even support a boot option for the USB ports.

I think they likely would a pentum4 or atholon64/seperon or newer will very likely have usb option.  Pentum3 or atholonXP might be hit or miss but thous i think have been thrown out by most people long ago.
Title: Re: Dumpster PCs
Post by: Alex Eisenhut on August 27, 2014, 06:49:35 pm
Here's one

http://www.memtest86.com/ (http://www.memtest86.com/)
Title: Re: Dumpster PCs
Post by: hans on August 27, 2014, 08:07:51 pm
IMO troubleshooting PC hardware is a big PITA, where instability/crashes are hidden between undocumented or just pointing in the wrong direction.

If board doesn't post/boot; MB, Graphics or CPU faulty is most likely faulty. Or just plain the power supply. Strip machine down, swap individual components to diagnose which one is faulty.
Some "enthusiast PC" boards have some indicators (2x 7-segment display on board) with POST status codes. If the board hangs, it shows an error code which can be used for diagnosis. Unfortunately, great idea, but only a handful of modern/expensive boards feature this.

Instabilities/(pseudo-)random crashes can be caused by various components, from a bad driver (practically any vendor) to an underrated power supply, to heat issues, RAM errors (memtest86 - even 1 error is a no-go) , or faulty hard drives (bad sectors, crashing SSD firmware, etc).

All in all expect to spend some good (more valuable) time at a machine that doesn't work. At least that has been my experience in most computer trouble.

If it does seem to work, let it do a couple of hours to a couple of days of memtest86+, plus a soak test with some kind of stress test like Prime95. This will hopefully make sure the system is still stable at peak load and temperature for long periods.
Title: Re: Dumpster PCs
Post by: NiHaoMike on August 28, 2014, 04:31:41 am
Knoppix. It includes memtest86+ in the ISO as well as some screensavers that can easily load down older GPUs. You can add Prime95 on a USB drive for a complete CPU test.
Title: Re: Dumpster PCs
Post by: Bukurat on August 28, 2014, 06:09:16 am
If a motherboard won't boot you still do some tests by using a POST debug card. During POST the bios will output a series of letters and numbers to port 80, you can read these with a suitable debug card to find out where its stopping. 
Here is some information from 1998.  http://bbright.tripod.com/information/postcard.htm (http://bbright.tripod.com/information/postcard.htm)
I think I still have one here somewhere.
Title: Re: Dumpster PCs
Post by: westfw on August 28, 2014, 08:07:36 am
Quote
IMO troubleshooting PC hardware is a big PITA
Yeah; you can try to boot one of the live CD linux systems, or something like systemRecoveryCD (also linux, but with debugging/recovery tools.)  But if it doesn't work right away, it's not worth spending much time on.
(There are some very minimal linux systems: "tomsrtbt" used to fit on a 1.4M floppy (I don't know if it'll support modern post-floppy systems.  But there are also DSL and others.  Maybe cool if you want to run the machines as tiny control machines. ) Personally, I've been putting PCs back into the dumpster recently.  They're not worth the space they take and the power they use.  Not when you can get relatively modern refurbished PCs for less than $100, and new laptops for about $200, plus RPi, BeagleBone, android tablets, and so on.)
Title: Re: Dumpster PCs
Post by: edavid on August 28, 2014, 04:48:35 pm
If a motherboard won't boot you still do some tests by using a POST debug card. During POST the bios will output a series of letters and numbers to port 80, you can read these with a suitable debug card to find out where its stopping. 

Has anyone ever fixed anything by using one of these cards?  I have found them completely useless.
Title: Re: Dumpster PCs
Post by: StubbornGreek on August 28, 2014, 06:06:31 pm
If a motherboard won't boot you still do some tests by using a POST debug card. During POST the bios will output a series of letters and numbers to port 80, you can read these with a suitable debug card to find out where its stopping. 

Has anyone ever fixed anything by using one of these cards?  I have found them completely useless.

The motherboard speaker (you can install one if there isn't one attached to the mb pins to begin with) will give you all the information you need.

As far as software, you've been given some quality (non-problem specific) suggestions. Let us know more about the 'symptoms' so we can help; I'm confident that there is a solution to your problem...
Title: Re: Dumpster PCs
Post by: Bukurat on August 29, 2014, 12:01:05 am

Has anyone ever fixed anything by using one of these cards?  I have found them completely useless.

Back in 1992 when we received this board for evaluation we were primarily engaged in maintaining  a number of 80286 based computers that ran xenix. Ancient technology by today's standards and as slow as a wet week but had to be kept going.  We used the board on a few occasions to pinpoint bad chips. Nothing that couldn't be done with the speaker but reading 2 characters on a display is a bit easier than interpreting a string of long and short tones.


Other than that, no.
Title: Re: Dumpster PCs
Post by: G7PSK on August 29, 2014, 08:51:37 am
I just use a live CD or DVD of Linux if it doesn't boot to this its not worth bothering with. Most often its the hard drive is either bust or been removed. Noticed that some computers will not boot to bios with a dud HD installed.
Title: Re: Dumpster PCs
Post by: StubbornGreek on September 01, 2014, 12:46:59 am
I just use a live CD or DVD of Linux if it doesn't boot to this its not worth bothering with. Most often its the hard drive is either bust or been removed. Noticed that some computers will not boot to bios with a dud HD installed.

Never encountered this situation. BIOS is way before any disk priority is assumed. Even if the on-board RAID feature is used, you can still enter BIOS.

Has the OP had any success?