PSU or MOBO problem :sigh:

Bor · 08-26-2008, 08:07 PM

Hi,
I have a following problem.

High current is flowing on the PSU - MOBO +5Volts lines (those two marked as Vcc). It's so high that the plastic sorounding the pins was burned to crunky black. The PC was rebooting at random for last few days. CPU temperature was ok (checked with speedfan) so the problem lies somhere else. Additionally I checked voltages on the PSU - all is normal.

What might be the problem??

**peterhuang913** · 08-26-2008, 08:48 PM

How can we tell you the problem if you don't tell us what you have?

Tumbleweed36 · 08-26-2008, 08:58 PM

Look in your bios and tell us what the voltages are and be sure to list the specs as requested by Peterhaung913.

Bor · 08-27-2008, 08:01 PM

Ok, here goes the config.

CPU : Athlon XP 1600+ (very old stuff :) )
MOBO: Soltek SL-75DRV5
RAM : 512+256 DDR
GFX : Radeon 9200 LE
SND : SoundBlaster Live Value
ETH : 3Com ethernet 10/100
HDD : total 3 drives Samsung 160 + Seagate 80 and 120

VOLTAGES in BIOS:
generally all in the range of ATX spec with exception of +5V which was at the level of 4.2V and slightly fluctuating.

All temperatures in normal range (at least normal for me and this computer) CPU ~67C and two others ~45C

I turned the computer on, went to bios and left it like that observing the changes and then after about 2 minutes the pc restarted. Then I went to bios again, and wait. After next few minutes everything was ok - i mean the pc was working - but I found out that the PSU-MOBO pwr cables were quite hot. I turned the pc off and found that +5V lines are exceptionally hot and that the plastic sorounding the pins in the plug is burned to coal. All four VCC lines are affected but only the two at the corner of the plug were burned [photo]

After that I checked the voltage on the disconnected PSU and everything was in acceptable range. All +5V lines were at 5.069V level.

I have no idea what might be wrong. The configuration of the computer is the same for about 1.5 years. No changes at all. And the problem emerged few days ago. All started from reoccuring reboots.

Do you have any hints?

CJRodman · 08-28-2008, 10:53 PM

get a new psu+mobo. they are cheap these days, 60 bucks and your set

Tumbleweed36 · 08-29-2008, 04:15 AM

My guess would be the PSU, because as they age, they begin to put out sporatic voltages and that can cause a multiple of problems. Think I would try a new power supply in there.

08-26-2008, 08:07 PM	#1 (permalink)
Bor Registered User Join Date: Aug 2008 Posts: 2 OS: winXPsp2	PSU or MOBO problem :sigh: Hi, I have a following problem. High current is flowing on the PSU - MOBO +5Volts lines (those two marked as Vcc). It's so high that the plastic sorounding the pins was burned to crunky black. The PC was rebooting at random for last few days. CPU temperature was ok (checked with speedfan) so the problem lies somhere else. Additionally I checked voltages on the PSU - all is normal. What might be the problem??

08-26-2008, 08:48 PM	#2 (permalink)
peterhuang913 TSF Enthusiast Join Date: May 2008 Posts: 946 OS: XP Home SP2	Re: PSU or MOBO problem :sigh: How can we tell you the problem if you don't tell us what you have?

08-26-2008, 08:58 PM	#3 (permalink)
Tumbleweed36 Asst Manager Hardware Join Date: May 2005 Location: USA Posts: 19,488 OS: XP Professional	Re: PSU or MOBO problem :sigh: Look in your bios and tell us what the voltages are and be sure to list the specs as requested by Peterhaung913. __________________ ---------- I don't receive email notifications of replies to subscribed threads. (Internet provider policy) Therefore, if I don't respond to your post within 24 hours, please send me a reminder PM and include the link to your thread.

08-27-2008, 08:01 PM	#4 (permalink)
Bor Registered User Join Date: Aug 2008 Posts: 2 OS: winXPsp2	Re: PSU or MOBO problem :sigh: Ok, here goes the config. CPU : Athlon XP 1600+ (very old stuff :) ) MOBO: Soltek SL-75DRV5 RAM : 512+256 DDR GFX : Radeon 9200 LE SND : SoundBlaster Live Value ETH : 3Com ethernet 10/100 HDD : total 3 drives Samsung 160 + Seagate 80 and 120 VOLTAGES in BIOS: generally all in the range of ATX spec with exception of +5V which was at the level of 4.2V and slightly fluctuating. All temperatures in normal range (at least normal for me and this computer) CPU ~67C and two others ~45C I turned the computer on, went to bios and left it like that observing the changes and then after about 2 minutes the pc restarted. Then I went to bios again, and wait. After next few minutes everything was ok - i mean the pc was working - but I found out that the PSU-MOBO pwr cables were quite hot. I turned the pc off and found that +5V lines are exceptionally hot and that the plastic sorounding the pins in the plug is burned to coal. All four VCC lines are affected but only the two at the corner of the plug were burned [photo] After that I checked the voltage on the disconnected PSU and everything was in acceptable range. All +5V lines were at 5.069V level. I have no idea what might be wrong. The configuration of the computer is the same for about 1.5 years. No changes at all. And the problem emerged few days ago. All started from reoccuring reboots. Do you have any hints?

08-28-2008, 10:53 PM	#5 (permalink)
CJRodman Registered User Join Date: Aug 2008 Posts: 16 OS: xp	Re: PSU or MOBO problem :sigh: get a new psu+mobo. they are cheap these days, 60 bucks and your set

08-29-2008, 04:15 AM	#6 (permalink)
Tumbleweed36 Asst Manager Hardware Join Date: May 2005 Location: USA Posts: 19,488 OS: XP Professional	Re: PSU or MOBO problem :sigh: My guess would be the PSU, because as they age, they begin to put out sporatic voltages and that can cause a multiple of problems. Think I would try a new power supply in there. __________________ ---------- I don't receive email notifications of replies to subscribed threads. (Internet provider policy) Therefore, if I don't respond to your post within 24 hours, please send me a reminder PM and include the link to your thread.