Antec TP480w a dud????

[mouawad]

Just got the above PSU today after having freeze problems with my Enermax 350w powering a p4 2.8c @ 3.6+ on an Abit IC7-G

Rails on my Antec are as follows @ idle at all speeds in MBM
12v @ 11.77avg same in BIOS goes as low as 11.60 under load
5v @ 4.92 avg as low as 4.85 under load
3.3v 3.22 avg as low as 3.18 under load

This is not looking good is it ???? I am still getting freezing problems, which only happen under 100% load, when posting past 3640mhz. The processor is being kept cool by a Prometeia MAch II which never goes above -3 even under 100% load so temps aren't a problem either are more volts as these seem to make little difference with these C steppings. The fact that i can use IE fine and other basic tasks for hours without problems indicates to me that i am still not getting enough stable power from this PSU when put under heavy load.

Update - i've just booted into windows @ 2.8 and the 12v is still dropping as low as 11.61 when using IE. I know i should probably use a multimeter but i don't have access to one - i suspect this PSU is borked??? Anyone got answers either way?

[stan03]

your 12v looks pretty low, pm Gautam, hitechjb1, or larva they can help you out

[Gautam]

Yes, a multimeter would give a more accurate result. However, in your situation, it appears that it is in fact the power supply that's the issue. I'd be very skeptical about the 11.61v reading at idle and stock, however the low readings do seem to account for your problems at 3.6ghz. As a last resort, do try increasing the core voltage a touch. If it really does do nothing, considering RMA'ing your power supply.

[hitechjb1]

What Vcore to run 3.6+ GHz? How many hard drives, optical drives? What video card?

[mouawad]

my Enermax i had before was giving good rails but i dont think it had enuff juice at 350w to cope with my overclocking

i am running 2x120gb sata drives 1 dvd-r and a 9700 Pro this is running in a Mach II which runs off mains and only runs a couple of fans off the PSU.

i am wondering whether i have in fact hit the limit of the chip or whether its just this PSU thats at fault. Even though its obvious to be skeptical of bios/winbond temps the fact that my enermax rails were reported at ideal levels makes me think that this Antec is in fact not doing the job. If this Antec is running fine and the rails are falsely reporting low then my enermax rails must be adjusted upwards to give their true reading ...correct?? which means its real 12v was more like 12.2+ ....which seems to me to be pretty unlikely.

Or is 480w not quite enough to run at speeds of 3700+???

BTW - volts seem to matter little to the stability ... i can boot into windows at default volts @ 3800 and if i give it 1.6-1.7 actual it actually seems to have a more negative impact if any. I can also use IE and do regular stuff at this speed ...its just under load when i get my problems ....it seems a classic PSU problem to me, but maybe im just wishing that?!?!?!

[hitechjb1]

Let's look at the 12V current. From the Intel P4 data for a 2.8C at rated 1.525V, Icc is between 23 to 55.9 A. I estimated when overclocking to 3700 MHz at rated Vcore 1.525V, the current would be somewhere betwen 66.5-73.9 A. For P4 and any CPU, around max overclocking, raising Vcore (than necessary) may make things worst. If raising Vcore to 1.6V, at 3700 MHz, the max current would be somewhere between 69.7-77.5 A. And it would translate into 11.6-12.9 A on the 12V line of the PSU (assuming 80% efficiency).

Assumiing each HD takes about 2 A on the 12 V (I don't have the detail spec for the SATA HD). The few fans take 1-2 A on the 12 V line. The optical drive takes 1 A. So the max total 12 V current would be around 20 A. The TP 480 PSU is rated 22 A on the 12 V.

[mouawad]

think i may have found my problem

HT

since i've turned that off ive been running 100% load for 45 mins @ 265 FSB (3710) .....cpu is -7c.

i do remember reading a thread quite a while ago about HT causing problems with o/c but i don't know how widespread it is. Anyway with HT enabled at this speed i would crash within 1-2 mins so everything looks good so far.

[modenaf1]

http://www.theforumisdown.com/uploadfiles/0103/welcometotheforums.JPG

i was going to say hyper threading but you found it already. And, im no expert in this feild, but, I really hope that prometia has its own PSU right? If it is being run off of your computers PSU, that 99% chance that that is your problem.

so anyways, good to hear that it is working proberly and welcome to the forums!!

and, that is an awsome o/c! :thup: :thup: :)

[mouawad]

modenaf1 - yeh the prometeia is run from the mains outlet so at least i know that isn't causing any problems.

i have reached a max of 3710 (265FSB) with ram at 5:4 which is 100% stable. As soon as i nudge the FSB up even 1mhz it will freeze when benching after about 30-90 mins. I am not totally sure that the PSU is too blame for this, it feels to me like the NB is overheating - especially as i have only got a silent Zalman NB cooler on it.....which still works alot better than the standard POS HSF that comes on the IC7/IC7-G. So i think i will need to cool that a bit better and then i may be able to squeeze another 5-10 out of the FSB. I don't think i am reaching the limit of the CPU at 3710 because it would lock up or reset the machine automatically i would assume.....seeing how the temps are still -7 when it freezes. Because it's a gradual problem i am almost positive now that the PSU is working alright and the NB is just overheating.

Anyone else agree from what i've said????