Badcaps.net Forum
Go Back   Badcaps Forums > General Topics > General Computer Discussion
Register FAQ Calendar Search Today's Posts Mark Forums Read

 
Thread Tools Display Modes
Old 02-17-2017, 04:32 PM   #41
Spork Schivago
Your Awesomeness
 
Join Date: Mar 2012
City & State: Corning, New York
My Country: United States of America
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 4,517
Default Re: Suggestions for an HP M3970CM repair.

I think that little bastard on e-bay lied. I don't think there was an error copying files message when he was using this last. I think this entire board is deader than the other one. The new used CPU came today. I switched them out, still deader than a doornail. The last board and CPU, the bad ones, the CPU at least attempted to spin. Nothing! I verified the PSU is still good. I tried jump starting it, making sure the power button wasn't bad. I removed and unhooked everything, including the CPU and case fan, RAM, hard drives, and video card. Absolutely nothing!

Now I'm going to have to pull the board and start checking the fuses. This irritates me. If he had said the board is completely dead, I wouldn't have bought it. But saying the hard drive error, I knew there was some life in the board, worst case, I transfer some components from one board to the other. What a mess!

Now the question is should I contact him and ask if he lied? Even though it was being sold as-is, if he did in fact lie, then e-bay will side with me for him selling an item not as described. I honestly can't see what else could be wrong. With no RAM, it should at least do SOMETHING!!! Even if the RAM is bad, removing it, I should at least get SOMETHING!!!! But absolutely nothing. Fans don't even jerk with this board.

It's very frustrating and now I'm out 40$. And, of course, there's good chances now that Agent24 was right and the CPU is in fact still good. So that's another 60$ that might not had to have been spent. Man, I really hate liars. Even if I fix the board, there's a good chance that CPU didn't have to be bought.
__________________
-- Law of Expanding Memory: Applications Will Also Expand Until RAM Is Full

Last edited by Spork Schivago; 02-17-2017 at 04:56 PM..
Spork Schivago is offline   Reply With Quote
Old 02-17-2017, 05:36 PM   #42
Spork Schivago
Your Awesomeness
 
Join Date: Mar 2012
City & State: Corning, New York
My Country: United States of America
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 4,517
Default Re: Suggestions for an HP M3970CM repair.

I used the DMM and verified there's ~2.93VDC on the PWR+ pin on the front panel connector. That means at least some fuses are good. I haven't removed the board yet, but I'm thinking this guy who sold me the board did the same thing that my friend did.

I'm using the pinout diagram located here:

http://www.tomshardware.com/answers/...therboard.html

and taking a conductor and shorting out PWR+ and PWR- (in the picture, they refer to it as PW+ and PW-). That should be enough to rule out bad switch. This is really frustrating!
Spork Schivago is offline   Reply With Quote
Old 02-17-2017, 06:24 PM   #43
ChaosLegionnaire
HC Overclocker
 
Join Date: Jul 2012
City & State: Singapore
My Country: Singapore
Line Voltage: 240VAC 50Hz
I'm a: Hobbyist Tech
Posts: 1,391
Default Re: Suggestions for an HP M3970CM repair.

sorry to hear that. should have just junked the whole system from the get-go instead of repairing it esp. since its oem crap and a hp to boot. should have just told the customer u cant fix it and dont have the parts to test it. recent modern hardware is just terribly built.
Quote:
Originally Posted by Spork Schivago View Post
Now the question is should I contact him and ask if he lied?
that depends on his feedback. does he have anything less than 100% feedback, anything less than stellar immaculate 100% feedback, is valid grounds for a dishonest and not as described complaint.
ChaosLegionnaire is offline   Reply With Quote
Old 02-17-2017, 06:49 PM   #44
Spork Schivago
Your Awesomeness
 
Join Date: Mar 2012
City & State: Corning, New York
My Country: United States of America
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 4,517
Default Re: Suggestions for an HP M3970CM repair.

Quote:
Originally Posted by ChaosLegionnaire View Post
sorry to hear that. should have just junked the whole system from the get-go instead of repairing it esp. since its oem crap and a hp to boot. should have just told the customer u cant fix it and dont have the parts to test it. recent modern hardware is just terribly built.

that depends on his feedback. does he have anything less than 100% feedback, anything less than stellar immaculate 100% feedback, is valid grounds for a dishonest and not as described complaint.
99.9% feedback, 2 negative, 1 neutral in the last 12 months, 744 positives.

I told him I didn't think it was worth repairing, but I guess he promised it to some guy. I don't know for certain, but I'm getting the feeling there was some sort of deal made and this other person was supposed to get the PC for payment. I told him we could build a nicer one for a cheaper price, but he insisted on this one.

I tested all the fuses, they're good. I'm assuming (which isn't the best idea!) that a bad cap would still let the computer turn on somewhat, but a shorted cap might not. Can I just measure continuity across the various caps and look for a short to GND? Or to truly see if they're shorted, do I need to pull everyone and test with my ESR meter?

Also, on the old board, I pulled an SOT-23 package to test with my DCA meter. I'm going to see how hard it is to put back on. It tested fine, some N-Channel MOSFET by the CPU. Do transistors ever short to GND? If so, can I test just by measuring the continuity between the various pins or do I have to pull every one of them to test?

Thanks!
Spork Schivago is offline   Reply With Quote
Old 02-17-2017, 06:53 PM   #45
Spork Schivago
Your Awesomeness
 
Join Date: Mar 2012
City & State: Corning, New York
My Country: United States of America
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 4,517
Default Re: Suggestions for an HP M3970CM repair.

I'd like to add there's a row of solder pads in what I consider the front of the board (the side closest to the front of the case). They say various things. VRMGND, PS_ON....there's two pads for each. The 20 / 24-pin ATX power supply connectors also have a PS_ON signal. I'm wondering if I jumped something to that if I could force the PSU on. If I remember correctly, I ground it to turn it on.

I should probably hook up a PSU to the board again and check for the various voltages. +12VDC, +5VDC, +3.3VDC, -12VDC. Maybe I'd find one that isn't there and that would give me a clue.

Last edited by Spork Schivago; 02-17-2017 at 07:11 PM..
Spork Schivago is offline   Reply With Quote
Old 02-17-2017, 08:26 PM   #46
Spork Schivago
Your Awesomeness
 
Join Date: Mar 2012
City & State: Corning, New York
My Country: United States of America
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 4,517
Default Re: Suggestions for an HP M3970CM repair.

The original board, I pulled the heatsink off the northbridge. It's an AMD 215-0716050. I believe that's the RX980. It looks pretty bad. I'm pretty certain he fried that. It's only 17$ for a new AMD 215-0716050 Northbridge, but I need my BGA rework station hooked back up to replace it, and that can't happen until we upgrade the electrical, which won't happen until we get our taxes back, which won't happen until we submit them. Man, I really miss that BGA rework station.

Last edited by Spork Schivago; 02-17-2017 at 08:29 PM..
Spork Schivago is offline   Reply With Quote
Old 02-17-2017, 08:41 PM   #47
Spork Schivago
Your Awesomeness
 
Join Date: Mar 2012
City & State: Corning, New York
My Country: United States of America
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 4,517
Default Re: Suggestions for an HP M3970CM repair.

I was looking over the board, I noticed the AMD 215-0716050 supports jtag. I see on the bottom of the board 20 pads, 2x10. My DMM's 9v is dying and tomorrow I'll go grab a new battery and probe them, but I'm wondering if that's a standard 20-pin ARM JTAG there, like this:

http://www.micromouseonline.com/wp/w...0-pin-DIL1.png

It's got a J1 on it, in green. It's on the bottom side of the board and looks like the JTAG pads I've seen in the past. Not sure how it'd be useful though, I'm not very good at using OpenOCD.

Even if it's a different format, if the pads are for jtag, maybe I can figure out what pins go where and try to hook up to JTAG device on the "good" board.

Last edited by Spork Schivago; 02-17-2017 at 08:49 PM..
Spork Schivago is offline   Reply With Quote
Old 02-18-2017, 02:24 PM   #48
Spork Schivago
Your Awesomeness
 
Join Date: Mar 2012
City & State: Corning, New York
My Country: United States of America
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 4,517
Default Re: Suggestions for an HP M3970CM repair.

I am finally making some progress! Last night, I didn't have a spare 24-pin power supply to test with, but I had a 20-pin. Normally, these 20-pins will still power a 24-pin board. Today, I decided I'd take the original PSU again and check every pin with my multimeter. Maybe a ground isn't there? Maybe one of the 5V is there but not another? I'm not sure exactly how my tester tests stuff. There's also a little turn dial on the back of the PSU. I turned that up to high.

I hooked the 24-pin in my tester, I hooked the 4-pin CPU connector into my tester, I turned on the PSU on the back and my power supply testers starts beeping. I look down, the 5V is going all over the place. 5V, 4V, 3V, 5V, 4V, LO, all kinds of weird shit. I turn off the PSU, unhook the 4-pin CPU, turn it back on, my power supply tester doesn't even light up, the power supply doesn't even turn on. I wait a bit, try again, this time the PSU turns on but my tester just beeps, nothing on the screen.

Now I'm going to take the PSU out and tear it apart and see what we find. Hopefully, this bad PSU didn't fry the possibly good board and good CPU. I feel so bad calling the original seller a prick now. I don't think he lied. I really don't think he lied at all.
Spork Schivago is offline   Reply With Quote
Old 02-18-2017, 03:56 PM   #49
Spork Schivago
Your Awesomeness
 
Join Date: Mar 2012
City & State: Corning, New York
My Country: United States of America
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 4,517
Default Re: Suggestions for an HP M3970CM repair.

I tear the PSU apart, I can count at least 3 bad, swollen caps. Thinking of going to the power supply thread and asking for help with recapping it. There's a really large 400VDC 390uF filter cap (I believe it's called a filter cap). I'm wondering if I should be replacing that one as well. There's also a bunch of really small ones, I wonder if they should be replaced or just the larger guys. From my experience, those little ones hardly ever fail.

I guess these are questions for the Power SUpply thread though. Once I get the PSU fixed, I'll be back to let you guys know if the motherboard works! Worries me a little the PSU tester said it was good the first time and now it shows it's bad. This is the third time I've had the tester hooked up. Two times it read fine, this time, not so much!
Spork Schivago is offline   Reply With Quote
Old 02-18-2017, 10:06 PM   #50
delaware74b
Badcaps Veteran
 
delaware74b's Avatar
 
Join Date: Apr 2009
City & State: Delaware
My Country: USA
Line Voltage: 480VAC 60Hz or Less
I'm a: Knowledge Seeker
Posts: 569
Default Re: Suggestions for an HP M3970CM repair.

Sportk - recap power supply, everything except the large filter cap unless it's swollen.
__________________
Stupidity should be a crime, especially for drivers. I have NO patience for them.
delaware74b is offline   Reply With Quote
Old 02-19-2017, 12:17 PM   #51
Spork Schivago
Your Awesomeness
 
Join Date: Mar 2012
City & State: Corning, New York
My Country: United States of America
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 4,517
Default Re: Suggestions for an HP M3970CM repair.

delaware74b,

I started a new thread in the Power Supply forum, asking for help with picking out good quality caps and asking for suggestions on the recap. Thanks!
Spork Schivago is offline   Reply With Quote
Old 03-17-2017, 10:07 AM   #52
Spork Schivago
Your Awesomeness
 
Join Date: Mar 2012
City & State: Corning, New York
My Country: United States of America
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 4,517
Default Re: Suggestions for an HP M3970CM repair.

I've been a bit sick, but I managed to recap the power supply yesterday. I put it in the PC, after testing it with my power supply tester. The tester shows it's good. I hook everything up and hit the power supply, the fans all turn on but it doesn't post. I start troubleshooting. If I turn off the PC, the PSU fans still run. Wondering if I did something wrong there or if it's supposed to run until it reaches a certain temp.

I remove all the RAM and turn it on, expecting a beep. Same as before, all fans turn on, no beeps, no POST. There's one of those cylinder looking built-in speakers, so it should be beeping. Then I remove the video card and turn it on. It turns on and then shuts off!!! But the power supply fans still run. I add the RAM back but keep the video card out, same thing. Turns on and then off.

I'm going to put the video card in another system to test. My wife's going to pick up a new stick of DDR3 on her way home from work, just so we know we got a working stick.

This things turning into a nightmare!
Spork Schivago is offline   Reply With Quote
Old 03-17-2017, 12:04 PM   #53
Spork Schivago
Your Awesomeness
 
Join Date: Mar 2012
City & State: Corning, New York
My Country: United States of America
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 4,517
Default Re: Suggestions for an HP M3970CM repair.

I put the video card and PSU in another PC. I've verified the power supply was rebuilt correctly and that the external video card works properly. My wife will pick up a stick of DDR3 from Staples on her way home from work. I could only find an 8GB stick. Checked Staples, Walmart, and BestBuy. Bestbuy had the same stuff that Staples had but wanted 80$!!!! instead of 55$!!!. Walmart didn't have any, unless I wanted to order it.

So we'll have a new 8GB stick to test with soon. At least now I know the video card and power supply are good.
Spork Schivago is offline   Reply With Quote
Old 03-17-2017, 02:29 PM   #54
Spork Schivago
Your Awesomeness
 
Join Date: Mar 2012
City & State: Corning, New York
My Country: United States of America
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 4,517
Default Re: Suggestions for an HP M3970CM repair.

I've now replaced the RAM and it's still dead. So I'm going to switch out the CPUs. Maybe I accidently got them mixed up somewheres along the way and this is really the bad one? I dunno, but this is getting frustrating.

No unnecessary components are hooked up (DVD burner, hard drive, etc). Just the video card, RAM, and the wireless NIC that plugs into the motherboard, just like you see with laptops. The customer said if the WNIC isn't installed, it won't boot. Maybe I'll try removing it anyways, just to see if anything changes.
Spork Schivago is offline   Reply With Quote
Old 03-18-2017, 12:31 PM   #55
Spork Schivago
Your Awesomeness
 
Join Date: Mar 2012
City & State: Corning, New York
My Country: United States of America
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 4,517
Default Re: Suggestions for an HP M3970CM repair.

I'm finally making some progress. I put the old CPU back in (it's definitely the original CPU that's in now, the new one didn't do anything at all), and I get 5 long beeps. It's an AMI BIOS I believe.

I'm going to try putting the new CPU back in. Maybe it wasn't seated properly or something? At least I'm getting some beep codes now!
Spork Schivago is offline   Reply With Quote
Old 03-18-2017, 01:40 PM   #56
Spork Schivago
Your Awesomeness
 
Join Date: Mar 2012
City & State: Corning, New York
My Country: United States of America
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 4,517
Default Re: Suggestions for an HP M3970CM repair.

I put the new CPU back in, 5 long beeps. I think I'm now going to try swapping BIOSes. For the h8-1534, according to a guy on a forum, 5 long beeps means:
Code:
 Flashing failed (checksum error, corrupted image, etc.)
And although this is an H8-1414, I think the error might be the same. The original seller of this board said they got an error reading files. After talking to him, I'm pretty sure he didn't actually use this board, but just was selling it. He said he talked to his techs and they said they would have tried the same troubleshooting. HPs website for this board says the 5 beeps would be error reading files. Normally, a computer will turn on without any hard drive plugged in at all. And seeing how the hard drive is good, I'm assuming that error reading files means error reading parts of the firmware.

I've had trouble replacing those little 8-pin ICs before, but hopefully, I have enough experience now to remove one without damaging anything.

Wish me luck!
Spork Schivago is offline   Reply With Quote
Old 03-18-2017, 03:35 PM   #57
Spork Schivago
Your Awesomeness
 
Join Date: Mar 2012
City & State: Corning, New York
My Country: United States of America
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 4,517
Default Re: Suggestions for an HP M3970CM repair.

Okay, another small update. I got the known good BIOS chip removed. I couldn't get it removed using hot air. We tried being careful because there's a lot of plastic in that area (header pins, SATA connectors, etc). When it wouldn't come with the hot air, we switched to the micro soldering iron and used a small needle to bend each pin up. Got one side done. With the second side, we had some issues. So I added solder and bridged it on accident. Then went I went to touch the iron to it, all the pins came right up, which was good.

I've successfully dumped it. The chip shows a small pct on it and 25VF032B. The program I have to dump it shows an SST company makes a 25VF032B. I picked SST as a manufacturer and dumped it that way. It appears to have dumped successfully. A 4MB / 32Mb 25 / 26 SPI EEPROM. Now to remove the BIOS from the good board and switch them.
Spork Schivago is offline   Reply With Quote
Old 03-18-2017, 04:30 PM   #58
Spork Schivago
Your Awesomeness
 
Join Date: Mar 2012
City & State: Corning, New York
My Country: United States of America
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 4,517
Default Re: Suggestions for an HP M3970CM repair.

I have now successfully removed and dumped both chips. I've also downloaded the only BIOS listed on HPs website for this motherboard.

I've compared the two dumps from the original board and this board I bought off e-bay. They're very much different. The BIOS from HPs website compares very much the same as the original board, except near the end. I figure because this PC came with 8, the customers BIOS probably has some product key and serial number information. Unless HP had a previous BIOS they didn't list on their site, I'm thinking these 5 beeps really was from a bad flash.

I'm now going to write the original customers firmware onto the chip I just removed from the e-bay board and see what happens when I solder it back on.

Thanks!
Spork Schivago is offline   Reply With Quote
Old 03-18-2017, 06:54 PM   #59
Agent24
I see dead caps
 
Agent24's Avatar
 
Join Date: Oct 2007
City & State: Hiding inside a plated-through hole
My Country: New Zealand
Line Voltage: 230VAC 50Hz
I'm a: Hobbyist Tech
Posts: 4,543
Default Re: Suggestions for an HP M3970CM repair.

It might also be bootblock data that wasn't changed during an update.

I'd try the BIOS image from HP as a known good one myself, and keep the other two in case it doesn't work.
__________________
"Tantalum for the brave, Solid Aluminium for the wise, Wet Electrolytic for the adventurous"
-David VanHorn
Agent24 is offline   Reply With Quote
Old 03-18-2017, 07:36 PM   #60
Spork Schivago
Your Awesomeness
 
Join Date: Mar 2012
City & State: Corning, New York
My Country: United States of America
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 4,517
Default Re: Suggestions for an HP M3970CM repair.

Quote:
Originally Posted by Agent24 View Post
It might also be bootblock data that wasn't changed during an update.

I'd try the BIOS image from HP as a known good one myself, and keep the other two in case it doesn't work.
Would the bootblock be right in the beginning? I've already erased the one from e-bay (but I still have the dump, in case I need to go back). It's taking a VERY long time to write the new firmware. I think this might have something to do with the CH341A programmer I'm using. I think it's got a design flaw. There's a jumper that's supposed to allow us to switch between TTL and CMOS logic, but if it's set towards the 3.3V, it doesn't work at all.

A guy on youtube figured it out and said with this one, you need to have it set on the 5V, regardless of what the chip is expecting. That scared me a bit but seemed to work. I don't see my device as a serial device, just an USB EPP/I2C device, so I cannot set baud rate or anything. It's been writing for more than 3 or 4 hours now. It's at 88% now though.
Spork Schivago is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



Badcaps.net Technical Forums 2003 - 2019
Powered by vBulletin ®
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
All times are GMT -6. The time now is 02:14 AM.
Did you find this forum helpful?