Could a 460watt PSU hamper my overclock with this setup?

sniper007 · 9 Oct 2006 at 16:49

Hi there.
Used to have a rig based around Ultra-D mobo, 2x1gig ram, Opteron 144, 600watt seasonic etc etc, and used to be able to hit 2.8ghz easily with my opteron, and usually could just about get 2.9 stable, but 2.95 was too much.

I now have a very similar rig but have downgraded slightly and the only thing that is different is the ram 2x512mb, and the PSU 460watt Akasa Paxpower silent jobbie.

I have downclocked my ram massively and know it is not this, and am running all the usual setup to overclock an Opty (LDT set correctly etc) and Im running extra volts on LDT and chipset like I used to (have tried varying amounts) and Im pumping up to 1.6 volts through the CPU and yet still I cant get stable at 2.5ghz. Im running 3 x HDDs, a DVD drive, a floppy, an x800 gto2. I thought a 460watt PSU could take all that ok, or is it likely to be this that is the weakest link, especially given that it is not as highquality as some of the PSUs out there.
One other clue (but not sure if this is just poor software readings) is that when I check CPuz and OCCT stress tests, they all report the Vcore to cpu as being lower than I set in the bios. i.e. Ill set 1.55 and it will state its 1.49 or something.

Any help much appreciated, as 6 months ago this opteron was flying.

Ta

mrthingyx · 9 Oct 2006 at 17:18

Interesting, as undervolting/overvolting is normally a motherboard issue..

A very poor but reasonable way of checking if the PSU is at fault (i.e. rubbish amperage per rail) is to load up a mobo-monitor during a run of Prime, Toast, etc. and check the rails: if they plummet, then the PSU will be at fault.

The PSU probably is the problem (assuming the same voltages are acheived, etc.) if the power delivered by the PSU is noisy or nice and smooth. I remember a demosntration on some website or another of 'clean' power delivery vs 'noisy' regarding overclocking and the difference was striking. Generally, higher quality PSUs are made so not only their power delivery is constant, but that it contains minimal interference, etc.

Having no experience with Akasa PSUs, but knowing that a cheap bajillion watt PSU is worth less than a high quality 300W PSU, I would say the PSU could probably be at fault. But in the grand scheme of things, does 100MHz really matter? Especially if you have to pay for a new PSU...

sniper007 · 9 Oct 2006 at 17:24

mrthingyx said:
Interesting, as undervolting/overvolting is normally a motherboard issue..

A very poor but reasonable way of checking if the PSU is at fault (i.e. rubbish amperage per rail) is to load up a mobo-monitor during a run of Prime, Toast, etc. and check the rails: if they plummet, then the PSU will be at fault.

The PSU probably is the problem (assuming the same voltages are acheived, etc.) if the power delivered by the PSU is noisy or nice and smooth. I remember a demosntration on some website or another of 'clean' power delivery vs 'noisy' regarding overclocking and the difference was striking. Generally, higher quality PSUs are made so not only their power delivery is constant, but that it contains minimal interference, etc.

Having no experience with Akasa PSUs, but knowing that a cheap bajillion watt PSU is worth less than a high quality 300W PSU, I would say the PSU could probably be at fault. But in the grand scheme of things, does 100MHz really matter? Especially if you have to pay for a new PSU...

Cheers for the reply. Tis not 100mhz though, its like 400mhz etc Im missing out on. Not sure really what difference I will see 2.5ghz vs 2.85ghz in gaming, but Im thinking it might help a bit. I wouldnt mind if my ram was poor (which it is tbh lol) but what counts with A64 overclocking is raw cpu clock and for some reason I seem to have lost out from what it could do in the past. Unless the CPU has "gone bad" since about 4/5 months ago when I last used it.

snowdog · 9 Oct 2006 at 17:55

Akasa psu's are high quality psu's, check everest for +12 V voltage when stressed, if its above 11.8 volts its not your psu.
Try it perhaps with your seasonic ??

EDIT: nvm i misread, you dont have your old stuff anymore, as the guy above said try prime95 psu test and also when doing that check all the voltages in the meantime with a program like asus probe or everest.

As for specs :

http://www.akasa.co.uk/akasa_english/spec_page/psu/spec_ak_p460fg_blv5.htm

It passed *****.net tests on the big psu review thing.

The second Pax Power is nickel plated for possibly the shiniest deep black coating ever to grace a range of power supplies. It's server-oriented like the previous 400W model and performed more than admirably. Voltages were fine even under a full 460W output power load (over 600W from the mains). The 120mm fan meant it was quiet and generally cool. Connectivity is fine, although Akasa leave off a PEG connector for the enthusiast considering one. Efficiency was as expected and overall it performed like a champ.

Recommended system: Mid-range to high-end desktop systems based around P4 (including high-speed Prescott), AMD Athlon Socket A and AMD Athlon 64 and Sempron on Socket 754 and Socket 939. Server systems due to SSI connector.