Is 11.93V close enough to 12?

[HankB]

Today is not a happy day. My home NAS is down since yesterday when it just dropped from sight for no apparent reason (no reboot, power cycle or other events that would correlate with this.)

This is an Intel Atom based mobo (BOXD525MW) with a couple drives in RAID1. It's running Linux (Debian Stable v7.4 with upgrades.)

It comes up as far as the GRUB menu and starts to boot. If I select one of the recovery options, it starts to load the initial RAM disk and seems to stall very repeatably about the time it would mount the hard drives. The last message on the console looks like it has just recognized the drives.

I tried checking the drives via a USB/SATA adapter from my laptop and they seem good as far as I can check. I can fsck the file system partitions and they check out OK. SMART diagnostics produce no hint of any error. I have difficulty accessing the data partition on either drive, but I suspect that this is a USB/SATA limitation (Drives are 2TB and 3 TB)

I tried booting a Debian Netinst CD via USB DVD reader and it did not come up but stalls when I try to load one of the installers. I'm running Memtest86+ right now to see if that reveals any problem.

I've pulled out my DMM and started probing various connections on the power connector (w/out actually looking up what any of the pins should read. ) I get readings of 3.33V, 5.04V -4.97V and 11.93V. Those all seem like reasonable readings. 5.04V and 11.93V is also what I get at a Molex connector. IIRC I have a 400W or larger PSU on a system that doesn't break 45W at the wall while folding.

My next step is to pull the drives and put them in another working system to see if they come up. If so, then I have to suspect the motherboard itself.

Any suggestions for other troubleshooting tips and suggestions would be most welcome!

 

[Silver_Pharaoh]

That's within spec yep.

Quality PSU unit though?

+3.3VDC	± 5%      +3.135 VDC	+3.465 VDC
+5VDC	± 5%	  +4.750 VDC	+5.250 VDC
+5VSB	± 5%	  +4.750 VDC	+5.250 VDC
-5VDC 	± 10%     -4.500 VDC	-5.500 VDC
+12VDC	± 5%	  +11.400 VDC	+12.600 VDC
-12VDC	± 10%     -10.800 VDC	-13.200 VDC

 

[HankB]

Quality PSU unit though?

Antec True330 so I think yes (and not 400W, only 330W but should be enough.)

 

[RJARRRPCGP]

Antec True330 so I think yes (and not 400W, only 330W but should be enough.)

Sounds like it's a 2003, 2004 or 2002-period PSU. That period of Antec commonly has electrolytic caps going bad! The server going down increases the likelihood of the PSU having bad caps!

 

[HankB]

Sounds like it's a 2003, 2004 or 2002-period PSU. That period of Antec commonly has electrolytic caps going bad! The server going down increases the likelihood of the PSU having bad caps!

It could be that old.

How could I diagnose that?

thanks

 

[Silver_Pharaoh]

It could be that old.

How could I diagnose that?

thanks

Check for bulging caps and/or ones that already exploded/leaked.
See if you can shine a flashlight in the vents to see.

 

[mimart7]

In general it's not a good idea to disassemble a psu. It can be dangerous. If that psu is 10 years old, time to swap it out for a new one.

 

[RJARRRPCGP]

With it unplugged, inspect the secondary-side caps. Don't worry, the bad caps, if any, are most likely on the cold side.

Primary caps rarely go bad.

 

[EarthDog]

10 year old PSU... time to buy another. Do not risk taking it apart to look at it. It can kill you.

 

[RJARRRPCGP]

10 year old PSU... time to buy another. Do not risk taking it apart to look at it. It can kill you.

Look through the vent and don't touch the primary side! Later PSUs are better, because of a bigger grill to shine a light through.

I would go to http://badcaps.net.

 

[ShrimpBrime]

10 year old PSU... time to buy another. Do not risk taking it apart to look at it. It can kill you.

+1 on that vote!

 

[Tech Tweaker]

In general it's not a good idea to disassemble a psu. It can be dangerous. If that psu is 10 years old, time to swap it out for a new one.

Unless you know what you're doing.

I know what I'm doing, so I've disassembled quite a few of them. With them unplugged from the wall for an extensive period of course.

As for this PSU, it looks like it was made from 2002 to 2005, only rated at 68% efficiency.

Yeah, it's probably time to junk it and buy a new one.

 

[RJARRRPCGP]

Unless you know what you're doing.

I know what I'm doing, so I've disassembled quite a few of them. With them unplugged from the wall for an extensive period of course.

As for this PSU, it looks like it was made from 2002 to 2005, only rated at 68% efficiency.

Yeah, it's probably time to junk it and buy a new one.

The label: If it's +5 V-heavy, then it's definitely a True Power version 1x, which is ATX-spec 1x. (Pre-24-pin ATX)

Probably was made for the power draw of many socket 462 motherboards.

All Asus socket 462 motherboards have the CPU off the +5 V rail.

Note that even during this period, Intel was running CPUs off the +12 V rail, which you can tell by the separate 4-pin power connector.

Thus, not recommended for an Atom, even though an Atom hardly uses squat.

But, a scant 68-percent?! That my friend reminds me of those cheap off-name PSUs getting tested.
And those PSUs weren't cheap at the time. The only thing that goes wrong, usually just the secondary caps after a while.

A recapped Antec True Power 1x should do well in revived old-schoolers.

 

[HankB]

More info. (I have been on vacation and out of town for other reasons and am now returning to work with this.)

Here is the PSU I have been using:


I did not open it up but peered in through the openings (fans) to see what I could see. It appeared that the caps I could see were OK. (I cannot find a purchase record for this unit.)

I tried plugging this PSU in:


It would not power up. I purchased this one in December of '04 so it is nearly 10 years old. It draws 3W when power is applied but will not turn on. Actually, if I turn the switch on the PSU off and wait for the indicator LED on the MB to extinguish and then turn on the PSU and hit the front panel power on button, the case fan spins a couple times and shuts off. That makes me think the system is not drawing enough power to satisfy the the OCZ PSU. (Using about 10% of rated otput.)

With the Antec the system draws 40W at the wall with just the MB and one case fan powered. Adding a drive takes that to 48W and then 45W.

Is the consensus still that I should replace the PSU? Would this be a good choice? http://www.newegg.com/Product/Product.aspx?Item=N82E16817139090 (Or would it not be happy running near 10% of rated capacity?)

Would this: http://www.newegg.com/Product/Product.aspx?Item=N82E16817182006
or this: http://www.newegg.com/Product/Product.aspx?Item=N82E16817371003
make more sense?

 

[Shell]

hec HP485D probably better than those, still not good though.

If the refurb CORSAIR was actually load tested it'd be by far the best.

 

[trents]

+ or - 5% is the general rule for acceptable PSU voltages but you would need to test that under load. There is a stick for doing this in the PSU section of the forum. If you first discharge the PSU's capacitors by unplugging the power cord from the wall and then pushing the computer's power button before removing it from the case it should be safe to dismantle it for inspection.

 

[EarthDog]

It is more than a general rule, it is the ATX specification (p. 22).

Also, just unplugging it and pressing the power button will not drain all the power in the caps. The (main?) cap holds a charge quite a while IIRC (I am regurgitating a post from BobN I believe).

 

[wagex]

if it is barely starting up with one psu and not starting with another try to unplug everything unnecessary (hdd's, usb devices (all), raid cards, the works) and try to boot it then, i had something weird happen where a good psu wouldnt even power up the machine while a cheap old antec would. problem then was a faulty usb adapter that was shorting the 5v good psu kicked off, cheap one didnt but i had issues.

 

[HankB]

if it is barely starting up with one psu and not starting with another try to unplug everything unnecessary ...

I pretty much did that. This is a pretty bare bones system with an Atom motherboard, two drives and a case fan. My testing included with both drives disconnected (but not the case fan.)

IAC, I've got another system cobbled together with my previous 'main system' mobo - running a Phenom II 820 x4. It boots right up on one of the drives so I know that the HD is not the issue (and it can serve as my NAS for the moment.)

That leaves me with either the Intel Atom mobo or the Antec PSU as possible culprits. Since the PSU can be replaced for less I think I will have a go at that. At least the Corsair 430W unit could be used as a backup PSU in my main system.

Thanks!

 

[HankB]

Got the new PSU in today (Corsair CX430.) Looks like it cuts the power usage at the wall about in half (21W mbo only.)

Otherwise no joy. It won't boot abything on a DVD/CD other than Memtest86+. Neither the install CD I used recently to update the OS nor an older Linux Mint CD comes up.

Looks like the motherboard is bad.