Erk - overloaded PSU?

[L337 M33P]

I am currently running this PC (rig 2) at the speeds in the sig below. Under Prime95 the followng voltages are seen in MBM5 - using the proper standard for Asus motherboards...
Line_____Low___ Avg____High
12V = 12.54 | 12.66 | 12.74
5V = 4.78 | 4.83 | 4.87
3.3V = 3.27 | 3.29 | 3.31

Using a 300W Chieftec PSU (came with case, stuff printed on side but not much in the way of certification) - it says "maximum load 300w" but all the rails add up to 350W. I am wondering if the 12V rail is high enough to cause damage or crispy components and should I load the 12V rail to bring it back within spec?

Plus is it worth getting another PSU if I want to hit 2.4GHz (with better cooling) - my dad doesn't seem to think so, and I tend to agree with him as stuff like Fortron and Antec in the UK is in excess of £50 for around 400W.


EDIT - checked with a DMM and the 12V is actually 12.60V and the 5V is 4.96V - at the end of a string of molexes with a HD and a fan attached on them.

[eobard]

I'd say your 5v is more of a concern based on the mini-chart thing you put up. Any system I've ever used had locked if the 5v gets below the 4.83v-4.85v range, even if it's only a slight dip. Maybe you could crack it open and dial down the 12v and up the 5v a bit if it's got pots in it. Just remember to let it sit unplugged for a while before opening it.

[L337 M33P]

I might do that as I have no intention of 5v modding my motherboard yet as per Hoot's guide, it's too new :)

If I were to open up the PSU, where would the pots roughly be located? I know what they look like and how to adjust them but what tells them apart from the 10 other pots in there?

[eobard]

Originally posted by L337 M33P
I might do that as I have no intention of 5v modding my motherboard yet as per Hoot's guide, it's too new :)

If I were to open up the PSU, where would the pots roughly be located? I know what they look like and how to adjust them but what tells them apart from the 10 other pots in there?
Every PSU is different, I couldn't exactly say where yours are (assuming you have any, some PSUs don't) but I'd start by looking at where the 5v and 12v wires are soldered into the board and then, if it's not too convoluted and crowded, trace back along the circuity until you get to a potentiometer. Then post pics asking if those are the right ones as a precaution, hopefully someone's done the adjustment to the same PSU that you have before and they can confirm that you have the right ones.

Or maybe you'll just get real lucky and it'll be clearly marked.

[L337 M33P]

Thing is, I don't have a digital camera...

Thanks for the advice though, will post an update if I manage to find the pots.

[eobard]

Originally posted by L337 M33P
Thing is, I don't have a digital camera...

Thanks for the advice though, will post an update if I manage to find the pots.
You don't have to put up a pic, but I really don't like advising someone to mess with something that could kill them if they get it wrong. In the least I suggest that if you do adjust the pots and you aren't sure you've got the right ones that you don't have your computer hooked up to the PSU, just short out the start jumper like it show in the sticky at the top of this area and connect a multimeter to one of the molex's to check the readings.

[L337 M33P]

I am not one to go and mess in PSUs that are "on" - I learned my lesson the hard way - result: One exploding linear regulator and a nice burn mark in the heatproof mat on the table. This was in a PSU of my own design for my audio amp that I built :rolleyes:

Hmm good tip instead of plug&pray short the green wire to ground - will do that.

EDIT - w00r due to my l33t searching skills I just found the manufacturer of my PSU - http://www.highpowersupply.com/product-ps-hpc300102-12v.htm Great brand :rolleyes:

[Oklahoma Wolf]

Sirtec is the actual maker of the PSU - Highpower is another of the names that uses their units.

These aren't the most powerful units around, so I'd suggest moving to a Fortron/Sparkle 530w or an Antec/Channel Well 430w or higher unit. You'll have a better chance of that overclock methinks.

Edit - just noticed cost is an issue... you should be able to find a Channel Well in the UK for cheaper than its Antec equivalent - they're hard to find here but I've heard of them being more widely available in the UK. The models I recommend are the CWT-430AS (or AD - dual fan) or better, or the CWT-450BS (or BD). Models with a P on the end have PFC IIRC.

[larva]

Two important points here:

Originally posted by L337 M33P
Plus is it worth getting another PSU if I want to hit 2.4GHz (with better cooling) - my dad doesn't seem to think so, and I tend to agree with him as stuff like Fortron and Antec in the UK is in excess of £50 for around 400W.
A desire to be cheap has no impact on physical or electrical realities.

Originally posted by L337 M33P
EDIT - checked with a DMM and the 12V is actually 12.60V and the 5V is 4.96V - at the end of a string of molexes with a HD and a fan attached on them.
Usually a 12V level this high is an indication of overload on one or more of the rails. The Sirtec supplies are not overly beefy, although decent quality. Given the overclock you are trying to achieve a stronger power supply is a very good idea. Although a 300 or 350W Fortron will hold up better than the Sirtec unit, It is a bit of a giant step sideways. I also feel the smart money is spent on a Fortron 530 or an Antec True Power 430 or larger. The load on the 12V line has gotton stiff enough that even the best of the 300W power supplies, the Fortron, is borderline for a serious overclocking effort. For those that already have the Fortron, by all means ride it as far as you can. And for those looking for the best power supply 30-35 USD will buy, it is without question the Fortron 300 or 350. But for those buying a power supply in the hopes of a stellar overclock, it's time to consider a stronger unit.

[L337 M33P]

Originally posted by larva

A desire to be cheap has no impact on physical or electrical realities.


:confused: you got me - I comprehend it not

It seems I am stuck between a rock and a hard place. On the one hand I think that my current PSU is OK for it's job but it simply will not cope with an AMD XP at 2.4GHz. In fact it's crapping out now. So, I could get another cheap PSU which is within my budget but I will be stuck exactly where I am now, around 2Ghz. I don't think even the Fortron 300 is going to cope with it - at high MHz the CPU can pull a fair few watts, up to 1/3 the rating of the PSU. On the other hand I could buy an uber antec 480 or a Fortron 530 and completely max out my CPU, but at what benefit? Will I notice a big change? I am having trouble telling the difference from my Pally 2000 and my XP1800 @ 2600 speed.

[larva]

I was just saying that the fact that it costs more than you currently wish to spend doesn't mean the electrical realities of the situation don't say it isn't mandated or worthwhile. Only you can say if it is worth it to you, but likely you do value the extent of your overclock or you wouldn't be here and likely would have an entirely different computer.

Only you can decide if it a big enough priority to spend the money. Personally I feel it is and think you will too once you get over the financial aspect.

Granted machine speed is not entirely dependant on the cpu's frequency, but it certainly does help. If you can't tell the difference between your old stuff and the new, consider a faster hard drive subsytem. So much of what we perceive as speed in daily operation is the latency of the hard drive, give a certain level of core performance. A raptor for your boot drive might well be more noticeable to you in daily use if you are not doing much that is cpu-intensive.

Personally I don't like to run a supply at its maximum output. This is were poor regulation, supply failure, and damaged system components typically come from. Power supplies will stand being heavily loaded (or even overloaded) for some time, but not forever. As time goes on your power consumption will certainly increase so if your supply is showing its limits now I can't help but feel that a beefier unit is worthwhile long-term, whether it revolutionizes your use of the computer today or not.

[L337 M33P]

I do indeed value the overclock, but am still having trouble contemplating that amount of money for a PSU - even though I damn well know it's going to be of a better quality and allow me even more insane speeds. I will just sit and wait and when I get the need for speed again I will reconsider and see how much my priorities have changed.

I also think that HD speed is a factor, which is why I bought a Deluxe motherboard model with SATA :D

A PSU running at it's maximum output SHOULD be perfectly happy with it and not fail prematurely, but as a future electronic engineer I know that cost, time, and production efficiency factors can remove the certain amount of beefing up that engineers would like to have. So, some are better than others, but it is for those that you pay.

[dustybyrd]

I do indeed value the overclock, but am still having trouble contemplating that amount of money for a PSU - even though I damn well know it's going to be of a better quality and allow me even more insane speeds. I will just sit and wait and when I get the need for speed again I will reconsider and see how much my priorities have changed.

I also think that HD speed is a factor, which is why I bought a Deluxe motherboard model with SATA :D

A PSU running at it's maximum output SHOULD be perfectly happy with it and not fail prematurely, but as a future electronic engineer I know that cost, time, and production efficiency factors can remove the certain amount of beefing up that engineers would like to have. So, some are better than others, but it is for those that you pay.


first, SATA won't actually help that much unless you are transferring huge files, really huge...

a faster seeking, spinning hard drive like the 10,000rpm or 15,000rpm raptors will have a much more noticeable speed increase, particularly with boot times...

i think what larva was saying is that you need a bigger supply, even if it doesn't help your overclock that much...for the sake of the rest of your components health...

i personally don't believe that a huge power supply is going to allow for a big difference in overclockablility, if at all...

therefore, if you are short on cash...then get a high quality fortron 350 for this current machine....

however, if you can scrap up the doe, then get a more powerful high quality fortron 530 or antec true 480+ for possibly a higher overclock, but definitely the ability to add to and upgrade your system...