Is a PSU's life span effected by load?

Soldato
Joined
17 Dec 2004
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Now guys I could be totally barking up the wrong tree here, but.........

If you max out the wattage on a power supply, it wont last long, or it wont last as long, as using a power supply say like 50% of its power?
 
Regardless of the quality of the unit. I would have thought maxing something out would surely reduce it's lifespan. It's like anything I suppose.

If you redline a car everyday all day. It's going to die quicker than someone changing at 2000rpm.

Same with batteries, keep the torch on... it'll run out quicker. Keep the TV on all night every night. It will blow up sooner than one that is on once or twice a week.

That's my theory anyway. I have no scientific knowledge to back it up however.
 
Load affects heat and so cooling becomes more important. A cooler running PSU should last longer given the same components (assuming heat is detrimental to components).

It has been my understanding that it is heat which causes "wear and tear" to components as there are no moving parts to create any other type of wear (other than the fan).
 
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Load affects heat and so cooling becomes more important. A cooler running PSU should last longer given the same components (assuming heat is detrimental to components).

It has been my understanding that it is heat which causes "wear and tear" to components as there are no moving parts to create any other type of wear (other than the fan).

What about freezers? They blow up and have no moving parts.
 
Like these corsair psu's are guaranteed for 7yrs, now would they last that long if you maxed out the wattage on them, Im thinking no, but Im not sure, but most people buy much larger psu's then a pc needs anyhow

Like my 3yr old corsair 650watt psu is much too high for my pc needs, as pc only uses just over 300watts at load. So I think if I maxed out psu now, it would pop right away or pop in a few days.... But like I say I could be totally wrong.
 
Like these corsair psu's are guaranteed for 7yrs, now would they last that long if you maxed out the wattage on them, Im thinking no, but Im not sure, but most people buy much larger psu's then a pc needs anyhow

Like my 3yr old corsair 650watt psu is much too high for my pc needs, as pc only uses just over 300watts at load. So I think if I maxed out psu now, it would pop right away or pop in a few days.... But like I say I could be totally wrong.

Definitely not. They are stress tested and designed to run at the max. If you buy a 750W PSU and draw 700W from it. It's certainly not going to go bang anytime soon.

Have some faith :D
 
Phil was telling me that on my 650w XFX psu, that if I was drawing around 500w, that it's time to get a more powerful psu. My argument is that if a psu is rated at, in my case 650w, it should be fine and capable to draw that much if and when needed, or at least very close to it, even if it does shorten the lifespan a bit, no?
 
Phil was telling me that on my 650w XFX psu, that if I was drawing around 500w, that it's time to get a more powerful psu. My argument is that if a psu is rated at, in my case 650w, it should be fine and capable to draw that much if and when needed, or at least very close to it, even if it does shorten the lifespan a bit, no?

unless its more than 5 years old i wouldn't worry. most good brand PSUs will max out at about 10% above their listed wattage (700 - 750W for yours). running it at that level may reduce it's lifespan, but i wouldnt have though running it at or below spec would affect lifespan much at all.
 
It is load cycling that generally kills components, heat does not help though. Using continuous 50-75% of rated power it should last for years, using continuous 90% of rated power may reduce its effective life. therefore 500w from a good 650w is probably about ideal although upper limit for longevity.
 
unless its more than 5 years old i wouldn't worry. most good brand PSUs will max out at about 10% above their listed wattage (700 - 750W for yours). running it at that level may reduce it's lifespan, but i wouldnt have though running it at or below spec would affect lifespan much at all.

Thanks mate. That's interesting, I didn't realise good psu's can even go beyond the rated spec. Yeah, not worried about mine, it's only 9 months old since I bought it from OcUK and I doubt I draw much more than about 300 to 350w?
 
I can't see this making sense really.. If you bought a PSU spec'd at 850W and ran it at 850W and it died within a few months the the company would have to replace it under warranty and it would therefore cost them more...

kd

Very few people max out psu's tho, and to be honest I would feel a tad uneasy maxing out my psu over a long period of time, and would have to buy a more powerful one.
 
Very few people max out psu's tho, and to be honest I would feel a tad uneasy maxing out my psu over a long period of time, and would have to buy a more powerful one.

So you're saying you'd need to work out how much power your pc needs, then buy a psu that is 25 to 50% more powerful? ie, pc needs 400w, so buy a psu that is rated at 500 to 600w or even more?
 
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So you're saying you'd need to work out how much power your pc needs, then buy a psu that is 25 to 50% more powerful? ie, pc needs 400w, so buy a psu that is rated at 500 to 600w?

No you dont have to work it out at all, cos you kind of have a fair idea of what psu you need, and 9 out of 10, that psu will have much more power then your pc needs anyhow, so no probs.. Its only if you get into the muti gpu, you need to be a tad cautious, but then again, you would prob buy a stupidly high powered psu for that aswell.
 
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No you dont have to work it out at all, cos you kind of have a fair idea of what psu you need, and 9 out of 10, that psu will have much more power then your pc needs anyhow, so no probs.. Its only if you get into the muti gpu, you need to be a tad cautious, but then again, you would prob buy a stupidly high powered psu for that aswell.

I completely see your point, as if I wanted to upgrade to SLI, I'd probably invest in something like an AX850W/HX1050W/AX1200W...

All of these have a reasonable headroom for SLI - with only the AX850W being close to being pushed, but saying that the AX series is well known for fantastic quality, so I wouldn't have any worries about that either really....

Even though most people are cautious, I still don't think the well respected PSU makers - Corsair/OCZ/Seasonic/Antec would be suggesting you can run 850W of stuff off of their PSU's if you couldn't. Whilst most people probably would be running overpowered PSU's for their system and wouldn't be pushing the limits of the PSU there will always be people that do, and the PSU companies won't want to get a general reputation of having PSU's that fail under high load or under the kind of tests that plenty of reviewers put the PSU's through... Especially as their market-base is most likely quite tech-savvy and therefore word will spread quickly around the internet if people have issues...

Don't get me wrong, I'm sure that a higher usage would facilitate more heat and hence a shorter component life span, but in the same respect I wouldn't expect Corsair to give a product a 7 year warranty if they don't think it'll last that long, as PSU's are one of those goods you really can hang onto for yonks, and frankly if my PSU died after 6 years, I'd still happily get it RMA'd rather than get a new one... Which would be a cost to the company that surely they'd want to not incur...

kd
 
Unless you have a folding rig using the processors and gpu, who has their PC at peak power draw 24/7 anyway?

Even folding probably isn't equal to furmark + linpack. However you will still pick a PSU capable of doing this? This is what I use to ensure that my system is stable under peak load.
 
can't remember what site (it's one of the google results for "corsair ax750 review") but i read that the AX750 was measured at 890W before cutting out. that's pretty impressive, and goes to show that more expensive power supplies arent just a waste of money

i reckon 95% of users will never need more than an AX750. people who dont use more than one graphics card likely wont need more than 400W, even at peak load.
 
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