View Full Version : Is my power supply underpower if it is 350 Watt ?

10-12-04, 03:26 AM
Case: Antec SX835II, 350 Watt power supply
Motherboard: K8V
CPU: AMD 64 bit, 3400+
graphic card: Xtasy ATI 9800 PRO
Ram: 1 gigabytes
hard drive: One 80 gig SATA
3.5 inch Floppy disk: One
Modem card: One

CPU overclocking: 2433MHZ


I ran the configuration above for 4 weeks. Everything works
fine, and then all of a sudden, the two fan on the power
supply turn at a very low speed. The CPU fan also
run at low speed. The ASUS probe software indicates that
the three fan ran at below threshold.

When I played Commanche 4, it crahed after about 10 minutes of play. I then turned off CPU overclocking and uses the default configuration, but still does not solved the

Could it be that, it is underpower, but if so then why was this problem was not there on the first four weeks ?

Could it be that overclocking causes the fan controller on
the CPU or the fan controller on the motherboard to be damage ?

10-13-04, 09:30 PM
I never like the mother board to control the speed of the fans,but in the Bios there should be a place where you can increase the fan speed,I perfer hooking the fans up directly to the power supply and just hook the signal wire to the motherboard.But haveing a better power supply is always best to have when upgradeing and make sure the 12v line has at least 20amps or more and more the better.IMO the OCZ PowerStream makes some great P.S. for the money they cost and they have all the new connections and even the 420watt has 30amps on the 12v line.

10-14-04, 12:31 AM
Hi john19055 and thank you for replying.
The two fans in the power supply has only
one wire connect to the motherboard.

The CPU fan has one wire connect to the motherboard.

This is a standard configuration for all of the
motherboard that support 64 bit AMD CPU.

Therefore I do not have any choice as far as
how the power is connected to the fan.
I did switch the power supply with an identical
one that is new, but it still does not solve the
problem. Since it is not the power supply,
then could it be a component that control the
fan in the motherboard has been degraded?

10-17-04, 05:11 PM
I misunderstood I thought you were talking about the other fans,but if just one wire is hoohed up to the mother board,then it is just a signal wire to show the rotation of the fan,Most Power Suppies fans are control by heat of a thermal diode the cooler it runs the slower the fans runs and the hotter the fans speed up.If you put the same type of power supply back in it more than likely thats how it works.IMO I would have sugessted a more powerful Power supply since you are overclocking and needing more juice.If you just have one wire hooked to the motherboard for the CPU then thats just a signal wire that would'nt have nothing to do with have fast the fan spins.It would'nt matter what you have the M.B set at it will spin ever how fast the fan go's unless you can control it manually.The way you sounded was that you had the CPU fan hooked up to only your motherboard and not the Power supply with just the signal wire hooked up to the motherboard.The signal wire can not control your fan speed.