I use the same ration as the NEC does for normal electrical circuits, meaning 80 for continuous use. So for a 1000 Watt PSU, that would mean 800 watts are available for use in the system.
Now if you go over this by a small margin, say 820 to 840 watts you will probably be ok, but when you are starting to run at 95% load 24/7 things can get hot. While the first week or two you probably won't notice anything, overtime the components start to wear faster and wires get hot and you can have a fire hazard on your hands.
All around I think the 80% ration is the best rule of thumb to go by as saving a few dollars on a undersized PSU isn't worth the risk to you or your home.
Topic: 930~960w on 1000w psu. safe or not? (Read 1665 times)
it is better to leave a reserve of about 20%, it's not server power units that are designed for continuous work
I have 850W PSU running on full capacity for about 3 month non-stop and it works fine 
If your kill-a-watt is registering 850W, then you PSU is only supplying 680 Watts if we assume 85% efficient at max power. If you bought a larger PSU, say 1000W and ran the same rig (680W draw) it would register 740W on the Kill-a-watt. So you are throwing away 100W per hour. Which is about $130 a year at .15c/kwh. Which is the cost of a 1000w psu about
If your PSU is less efficient than 85% at max, then you are wasting even more money.
If you were running a 1000W PSU at full capacity, meaning your components are pulling 1000W from the PSU, your Kill-a-watt would register somewhere close to 1175W (assuming your efficiency dropped to around 85% at full power). That's a lot of wasted energy due to heat.
So even if your kill-a-watt is sayin 950W, your PSU is probably only delivering 810ish watts.
The 80% rule is a very broad term that came from server PUDs and also applies to household fuses which will flip due to excess heat generated by running continously at over 80% of the circuits max load (usaully 15a or 20a for households).
So even if your kill-a-watt is sayin 950W, your PSU is probably only delivering 810ish watts.
The 80% rule is a very broad term that came from server PUDs and also applies to household fuses which will flip due to excess heat generated by running continously at over 80% of the circuits max load (usaully 15a or 20a for households).
you need 96% efficiency PSU for that to work. Not very likely.
Why would you guys say only 80% is safe?! The products normally comes with 5 year factory warranty. I doubt the manifacturer would have that if it could not handle the load. I has a 650w PSU that had 700w load for 6 months, not a problem what so ever. I only changed it due to upgrading the entire system. I'd say you're safe. Even with overload. Just keep an eye on the temperature and smell.
Consumer-grade power supplies are designed to handle SHORT periods at high load, not continuous operation at full capacity or close.
Many automobiles are designed to be able to go 150+ MPH - but most of them don't handle doing 150 MPH for 24 hours at a time.
SAME ISSUE.
For reference - the Distributed.Net client, which is a cryptographic program that loads a CPU or a GPU down very heavily like mining software (which does VERY SIMILAR cryptographic work) used to be used by many sites in their testing AS A TORTURE TEST because of the level of load it put on components in a system.
it will not explode or burn you house, but most certanly it will die faster at 90% load. It is simple, it will just die faster.
It is safe. Modern power supplies are safe, but I think that the power reserve should be more. Your rigs are working 24/7 and that's a big load on the power supply. With such a load it will run continuously at the maximum limit. This leads to the fact that he will fail. It's enough to lose the stability of any tension.
From my experience, it is totally OK to exhaust PSU on this level. EVGA ones are prone to break before warranty though.
Unless it is a server-grade PSU, the 80% "ballpark" figure DOES apply for 24/7 operation.
It's not a hard and firm LAW, but it's a good idea to stay close to that ballpark for long-term reliability and STABILITY on a 24/7 mining rig.
Also, non-server power supplies DO have a "thermal derating" curve that often takes some digging to FIND, which is what leads to this rule of thumb.
Server-grade ones have the same curve - but it generally kicks in at quite a bit higher temp before their rating starts dropping.
It's not a hard and firm LAW, but it's a good idea to stay close to that ballpark for long-term reliability and STABILITY on a 24/7 mining rig.
Also, non-server power supplies DO have a "thermal derating" curve that often takes some digging to FIND, which is what leads to this rule of thumb.
Server-grade ones have the same curve - but it generally kicks in at quite a bit higher temp before their rating starts dropping.
Oh I agree you get better efficiency, and you will get much longer lifecycle of the PSU due to less load = less temperature output. But realistically, on a High quality PSU, it should not fail. Even if it does, although downtime sucks, it is under warranty and can be replaced. I'd be more concerned by having my PSU's horizontal if they have cheap sleeve fans. I wouldnt run them at 100% but if its a temporary situation then by all means there is no problem. Best practice, you are very correct, but for the "safe or not" question - I believe it is safe (if the PSU is rated highly on johnyguru)
Unless it is a server-grade PSU, the 80% "ballpark" figure DOES apply for 24/7 operation.
It's not a hard and firm LAW, but it's a good idea to stay close to that ballpark for long-term reliability and STABILITY on a 24/7 mining rig.
Also, non-server power supplies DO have a "thermal derating" curve that often takes some digging to FIND, which is what leads to this rule of thumb.
Server-grade ones have the same curve - but it generally kicks in at quite a bit higher temp before their rating starts dropping.
It's not a hard and firm LAW, but it's a good idea to stay close to that ballpark for long-term reliability and STABILITY on a 24/7 mining rig.
Also, non-server power supplies DO have a "thermal derating" curve that often takes some digging to FIND, which is what leads to this rule of thumb.
Server-grade ones have the same curve - but it generally kicks in at quite a bit higher temp before their rating starts dropping.
I see everyone posting 80%. Thats usually the number that relates to electrical loads. no more than 80% for a continuous load on the breaker. Does not apply to a PSU
Only Server Grade PSUs can be safely used 24/7 over 90% of the rated capacity.
The 80% rule of thumb if generally for efficiency.
I would say you can take it to 90% rating safely.
I would say you can take it to 90% rating safely.
Why would you guys say only 80% is safe?! The products normally comes with 5 year factory warranty. I doubt the manifacturer would have that if it could not handle the load. I has a 650w PSU that had 700w load for 6 months, not a problem what so ever. I only changed it due to upgrading the entire system. I'd say you're safe. Even with overload. Just keep an eye on the temperature and smell.
when it overload it shutdown, mine shutdown if i overclocked i notice later when i had my watt metter it did 1190w on a 1000w at the wall so it was to much
but it s safe the power supply just shutdown when it s to much or overheat
so i alos don't know why poeple speaking about 80% or what ever
Why would you guys say only 80% is safe?! The products normally comes with 5 year factory warranty. I doubt the manifacturer would have that if it could not handle the load. I has a 650w PSU that had 700w load for 6 months, not a problem what so ever. I only changed it due to upgrading the entire system. I'd say you're safe. Even with overload. Just keep an eye on the temperature and smell.
I have 850W PSU running on full capacity for about 3 month non-stop and it works fine
Sure to god hope that you do not have a family and kids living inside your home. If its just you, have fun!
I run the PSU at around 70% of rated number.
I have 850W PSU running on full capacity for about 3 month non-stop and it works fine
Sure to god hope that you do not have a family and kids living inside your home. If its just you, have fun!
it s safe if you have an corsair
running 2ring 5x380 on 1000w + fx8300 total 990w (the fx came later but i decrease the powerlimit on the gpu's)
power at the wall was 1080w for close to 2 years (i got my power meter few month back)
now i keep it under 1000 at the wall
but better buy 2x 700w it s the cheapest way, i will never buy an 1000w again now i notice that
running 2ring 5x380 on 1000w + fx8300 total 990w (the fx came later but i decrease the powerlimit on the gpu's)
power at the wall was 1080w for close to 2 years (i got my power meter few month back)
now i keep it under 1000 at the wall
but better buy 2x 700w it s the cheapest way, i will never buy an 1000w again now i notice that
I have 850W PSU running on full capacity for about 3 month non-stop and it works fine
For now.. Stay safe dude..
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