POWER SUPLY Question

[MS]

Hi, here goes my system
1xCore 2 duo 8500
2x2Gb Corsair DDR2
1x4850 PowerColor 512 PCI-E
1xSeagate 7K 200G sata
1xSamsung-Toshiba DVD writer
1xAsus P5Q p 45
1xPSU Thermaltake 480w (max 500) 2x80mm fans, 1 line of 12v - 18A
2x80mm fan chassis


I think my system could be underpowered.
The symptoms are: if I start the system after plug in the wal main
plug (230V), the computer starts and then turns itself off. After that,
returs on connecting its self on again. This is done in a period of time of
about 3-4 seconds. This is not most often to happen if the system is on
stand by mode.

According to the powercolor website my psu in not under rated for the
system.

Thanks in advance for some considarations
Manuel

 

[Dave]

Hi, here goes my system
1xCore 2 duo 8500
2x2Gb Corsair DDR2
1x4850 PowerColor 512 PCI-E
1xSeagate 7K 200G sata
1xSamsung-Toshiba DVD writer
1xAsus P5Q p 45
1xPSU Thermaltake 480w (max 500) 2x80mm fans, 1 line of 12v - 18A

This would be good, for a 300W power supply. (only 18A?!?, that's pitiful!)

2x80mm fan chassis


I think my system could be underpowered.
The symptoms are: if I start the system after plug in the wal
main plug (230V), the computer starts and then turns itself off. After
that, returs on connecting its self on again. This is done in a period of
time of about 3-4 seconds. This is not most often to happen if the system
is on stand by mode.

According to the powercolor website my psu in not under rated for the
system.

Thanks in advance for some considarations
Manuel

Well, that's hard to follow. But if it really has just ONE +12V rail of
only 18A, there is your problem. You are pulling at least 13A of current
off the +12V rail before your hard drives start spinning up. Momentary
power draw will go well over 18A.

A good 450W power supply will handle your hardware, but that assumes that
most of your available power is on the +12V rails. You want at least 30A or
better available on the +12V rails for your hardware. -Dave

 

[JR Weiss]

Hi, here goes my system
1xCore 2 duo 8500
2x2Gb Corsair DDR2
1x4850 PowerColor 512 PCI-E
1xSeagate 7K 200G sata
1xSamsung-Toshiba DVD writer
1xAsus P5Q p 45
1xPSU Thermaltake 480w (max 500) 2x80mm fans, 1 line of 12v - 18A
2x80mm fan chassis


I think my system could be underpowered.
The symptoms are: if I start the system after plug in the wal main
plug (230V), the computer starts and then turns itself off. After that, returs
on connecting its self on again. This is done in a period of time of about 3-4
seconds. This is not most often to happen if the system is on stand by mode.

According to the powercolor website my psu in not under rated for the system.

If you really have a single 18A 12V rail, it probably IS underpowered! My Antec
500 has 2 17A rails...

I'd try a more robust power supply...

 

[sheng.choi]

This would be good, for a 300W power supply.  (only 18A?!?, that's pitiful!)





Well, that's hard to follow.  But if it really has just ONE +12V rail of
only 18A, there is your problem.  You are pulling at least 13A of current
off the +12V rail before your hard drives start spinning up.  Momentary
power draw will go well over 18A.

A good 450W power supply will handle your hardware, but that assumes that
most of your available power is on the +12V rails.  You want at least 30A or
better available on the +12V rails for your hardware.  -Dave

Sounds like there's a short if its drawing 18-30Amps
Check and makesure nothing is touching.

 

[RobV]

Hi, here goes my system
1xCore 2 duo 8500
2x2Gb Corsair DDR2
1x4850 PowerColor 512 PCI-E
1xSeagate 7K 200G sata
1xSamsung-Toshiba DVD writer
1xAsus P5Q p 45
1xPSU Thermaltake 480w (max 500) 2x80mm fans, 1 line of 12v - 18A
2x80mm fan chassis


I think my system could be underpowered.
The symptoms are: if I start the system after plug in the
wal main plug (230V), the computer starts and then turns itself off.
After that, returs on connecting its self on again. This is done in a
period of time of about 3-4 seconds. This is not most often to happen
if the system is on stand by mode.

According to the powercolor website my psu in not under rated for the
system.

Thanks in advance for some considarations
Manuel

AFAIK, that's standard for ASUS MBs, at least starting with the P5B-Plus
that I have. When power is turned on after the PSU has not been plugged
in, the BIOS does a quick check to make sure all settings are to its
liking, then shuts off and turns on again, as you said, within a few
seconds. It has something to do with one of the built in "features".

If the PSU is left plugged in and the computer is shut down, but with
standby power still on, the system will simply turn on normally when the
power button (on the front) is pressed. My system has acted this way
since its initial build and through three BIOS updates.

As far as your PSU, one 18A rail for +12V is pretty weak for the load
you have. I have a Antec 430 watt PSU with two 17A +12V rails and 20A
each on the +5V and +3.3V rails. This is running a E6600 OCed to 3 GHz
with a 3650 ATI video card (no external power needed), 4 disk drives and
two optical drives. Although, the system does only use (at full CPU
usage) 230 watts.

 

[MS]

I suspect that in fact all wires black red yellow black (the psu has 3 sets)
go in to the psu and in to the same PCB. The source is the same. Also the
PSU label reports 12v 18 A. And finaly if i take off the 4850, the system
boots up only once.

 

[JR Weiss]

I suspect that in fact all wires black red yellow black (the psu has 3 sets) go
in to the psu and in to the same PCB. The source is the same. Also the PSU
label reports 12v 18 A. And finaly if i take off the 4850, the system boots up
only once.

As a couple of us surmised, the 4850 is obviously overloading the PSU.