antec 550w w/ LOW +5v rail

[OverKlocker]

i just noticed my +5v rail is running between 4.38 to 4.5 volts. not
sure how long it has been doing this, but my system has been a little
erratic over the last few weeks. normally my rig is rock solid. i
dropped my fsb from 200 back to 166, lowered my voltages back to
normal, disconnected all of my drives, and it is still on the low
side. i've had my antec true power 550w for about 2 years (maybe a
little longer). i thought i had a bad sata hdd or dvd burner, but
nogo. also my 3.3 is about 3.28, and my 12 is 11.37. my system and my
22"nec monitor are plugged into an APC Back-UPS Pro 1000. does this
sound like an RMA issue? seems like it to me. thanks in advance.

System Specs:
Asus A7N8X Del 2.0 (1007 Uber bios)
2500+ @3200+ (2.2 Ghz) 200 fsb
Thermalright SLK-800(A) (with AS3 and 80mm Denki fan)
1Gb Corsair pc3200 CL2 (2 sticks, with platnium heat spreaders)
Radeon 9700 Pro retail w/Aluminum ram sinks
22in NEC MultiSync FE1250
160 gig Maxtor SATA 7200rpm 8mb (XP Home SP1)
120 gig Maxtor PATA 7200rpm 8mb (data/backups)
Optorite dd0203 DVD burner
Artec 52x24x52 cdrw
Lian-Li pc10 (with window and light mod)
550W Antec True Power PSU
Phoebe v.92 pci modem
onboard sound
onboard nic

 

[_P_e_ar_lALegend]

Il Wed, 09 Jun 2004 04:30:37 -0500, OverKlocker ha scritto:

i just noticed my +5v rail is running between 4.38 to 4.5 volts.

Yes, that is the problem of your system instability.

Definitely broken PSU, I think. Or do u maybe have electrical problem in
the house?

 

[Nero]

Mine is at 4.84V and I have no problems.
Is that reading taken accross the - and + 5Volt rail or just the reading
your software tells you?
The only way to take voltage readings is by connecting a volt/test meter
directly to the leads/connectors on the PSU and not any other way.
What you see is after the MB regulates the voltage and not off the PSU.

 

[Nero]

You will only get a proper reading by connecting a test/volt meter across
the - and + 5 volt rail on the psu.
You cannot get an accurate reading by software or by what it says anywhere
else.
Mine is 4.84V and never any problems or slowing down.
The reading you see via windows or software is after the onboard regulation.

 

[_P_e_ar_lALegend]

Il Wed, 09 Jun 2004 13:07:41 +0100, Nero ha scritto:

You will only get a proper reading by connecting a test/volt meter across
the - and + 5 volt rail on the psu.

Well, hardware monitor, especially the one implemented in the bios, is not
perfect, but quietly accurated. If it say 4,3 and u have problem, it's
becouse it really is 4,3.

Mine is 4.84V and never any problems or slowing down.

4.84 is acceptable. 4.5 or less it's not.

the +5V is the most important reading for the stability and the
performance of the system: it handle the cpu power and have to be
perfectly stable and power enough.

My Enermax is actually 5.01 and system run great.

I had, in the past, low cost power supply with 4.7/4.8 reading and system
never been so stable like it's now.

I can say it's much more better to have a HIGH quality 250 PSU (I do have
an old 250 AOpen, rock steady at 5,03 running a totally stable 333/2400+
on an Abit board).

 

[Steve Birch]

My 550W enermax gave some very strange voltages (including low outputs) when
the +12V supply was not actually loaded hard enough.
I noticed that when I added more disk drives, the voltages became perfect.
If you read the specifications carefully, most power supplies have a minimum
load requirement on some of the outputs.
Just a thought....

- Steve

 

[DaveW]

Your power supply is failing.

 

[OverKlocker]

Il Wed, 09 Jun 2004 04:30:37 -0500, OverKlocker ha scritto:


Yes, that is the problem of your system instability.

Definitely broken PSU, I think. Or do u maybe have electrical problem in
the house?

power in the house is fine, plus my APC Back-UPS Pro 1000 should
condition the power if it was off slightly. more than likely, i'm will
be calling antec...LOL

 

[Nero]

No it's not................
like I said that reading is after onboard(MB)regulation.
I connected mine to a different MB and got a different reading.
Unload the 5v rail and then see.

 

[_P_e_ar_lALegend]

lots of good info here thanks, atx connector was already reseated,

also bypassed the APC unit (just in case), removed my modem, my backup
120gig hdd, and my dvd burner. so... running 1 hdd, 1 cd/rw, 9700pro,
i'm still getting 4.48-4.57 on my +5v rail.

Ask a friend for a new PSU to try or buy a new one: a system can't never
run stable with that low +5.

U need to check whats goin on.