need to replace power supply on legacy silent pc
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need to replace power supply on legacy silent pc
I designed my current PC in 2008 largely based on advice and information from this site. What an incredible resource! Amazingly, I'm still using this computer with all original components (except one HDD). The power supply fan has always been the largest noise source since there's no way to auto-control RPM's, but overall the system has exceeded my expectations. I'm still happily running XP.
The PS fan bearing is starting to wear, setting up an amplifying (and annoying) resonance with the case. Time to get a new PS. Rather than dive back into research mode, I'm hoping someone here can point me to a quiet replacement. I don't do overclocking or gaming. My setup is detailed in my sig. The CPU is rated at 110W and video card is rated at 32W max. As I recall, the 330W PS was larger than needed for this setup, and indeed I've never had any power issues.
The PS fan bearing is starting to wear, setting up an amplifying (and annoying) resonance with the case. Time to get a new PS. Rather than dive back into research mode, I'm hoping someone here can point me to a quiet replacement. I don't do overclocking or gaming. My setup is detailed in my sig. The CPU is rated at 110W and video card is rated at 32W max. As I recall, the 330W PS was larger than needed for this setup, and indeed I've never had any power issues.
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Re: need to replace power supply on legacy silent pc
Low capacity quiet PSUs are hard to find, particularly in U.S.A. where, you know, "bigger is better".
One of the best bets currently is the Bitfenix Whisper M 450W.
Second best may be the Seasonic G-360.
A third, less favourable (it's more expensive, it sports shorter cabling) option is the semi-passive Corsair SF450.
Last but not least, the quietest, active cooled option is perhaps the Be Quiet Straight Power E10 500W, but as a german product it's a tad overpriced there (even here in Europe, but other PSUs are overpriced as well).
One of the best bets currently is the Bitfenix Whisper M 450W.
Second best may be the Seasonic G-360.
A third, less favourable (it's more expensive, it sports shorter cabling) option is the semi-passive Corsair SF450.
Last but not least, the quietest, active cooled option is perhaps the Be Quiet Straight Power E10 500W, but as a german product it's a tad overpriced there (even here in Europe, but other PSUs are overpriced as well).
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Re: need to replace power supply on legacy silent pc
I recently repaired a 10+ year old Dell and I used this Seasonic PSU with great results:
https://www.newegg.com/Product/Product. ... 6817151086
300W 80 Plus Bronze $42 shipped - what's not to like?
https://www.newegg.com/Product/Product. ... 6817151086
300W 80 Plus Bronze $42 shipped - what's not to like?
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Re: need to replace power supply on legacy silent pc
Hi, I wouldn't replace the PSU, just the fan in it.
I put an Arctic F12 in a Seasonic S12 380w PSU and it works great, very quiet at idle. Although I haven't stressed it to know how much it can take.
Go with good 1200-1500 rpm fan, I like Arctic ones as they are good and very cheap on ebay (£3-4 each), and I think you will be fine. If the fan doesn't run at idle due to too low volts from the PSU you probably get away with it as once it gets worked harder the temp goes up and the voltage goes up and the fan starts. Others will disagree no doubt, but if you're going to replace the PSU do you have much to lose?
As you're not pushing the PSU with your system you should be fine using lower than original rpm fan.
I like to keep the RPM monitoring wire and route it to a motherboard header to see the PSU fan speed. If you do this you can monitor the PSU fan speed and if it gets close to the maximum of the fan you've swapped in you know the PSU has reached its limit for internal temperature.
As the S12II 330 you have is a decent PSU to start with it wouldn't expect you to have problems. For a while I had one driving an i7 2600K + GTX560Ti running folding at home pulling ~250w from the PSU so gave it a good work out and it was just fine doing it.
Regards,
Seb
I put an Arctic F12 in a Seasonic S12 380w PSU and it works great, very quiet at idle. Although I haven't stressed it to know how much it can take.
Go with good 1200-1500 rpm fan, I like Arctic ones as they are good and very cheap on ebay (£3-4 each), and I think you will be fine. If the fan doesn't run at idle due to too low volts from the PSU you probably get away with it as once it gets worked harder the temp goes up and the voltage goes up and the fan starts. Others will disagree no doubt, but if you're going to replace the PSU do you have much to lose?
As you're not pushing the PSU with your system you should be fine using lower than original rpm fan.
I like to keep the RPM monitoring wire and route it to a motherboard header to see the PSU fan speed. If you do this you can monitor the PSU fan speed and if it gets close to the maximum of the fan you've swapped in you know the PSU has reached its limit for internal temperature.
As the S12II 330 you have is a decent PSU to start with it wouldn't expect you to have problems. For a while I had one driving an i7 2600K + GTX560Ti running folding at home pulling ~250w from the PSU so gave it a good work out and it was just fine doing it.
Regards,
Seb
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Re: need to replace power supply on legacy silent pc
Nothing against fan swap, I myself did several ones, but, if you don't want to take into account a proper starting voltage, couldn't a failing PSU (in case) damage other parts?SebRad wrote:Others will disagree no doubt, but if you're going to replace the PSU do you have much to lose?
Instead of a sort of semi-passive behaviour, I would think to route the the replacement fan cable outside: I'm thinking to an ~800rpm fan driven by a 12V molex as an alternative option, as I guess there isn't a suitable fan header on that rig.
BTW, how does your F12 work in that 380? On/off?
Re: need to replace power supply on legacy silent pc
Thanks for the tips. I didn't even think about replacing just the fan. Of course!
The Arctic F12 is a PWM fan, right? I understand PWM fans can also be controlled via voltage. Does my power supply require PWM? If not, I have a spare Scythe SY1225SC12M (KAZE-JYUNI) that I could install. It was reviewed strongly on this site and has very low starting voltage (2.4V, see http://bit.ly/2kW2UGh).
The Arctic F12 is a PWM fan, right? I understand PWM fans can also be controlled via voltage. Does my power supply require PWM? If not, I have a spare Scythe SY1225SC12M (KAZE-JYUNI) that I could install. It was reviewed strongly on this site and has very low starting voltage (2.4V, see http://bit.ly/2kW2UGh).
Re: need to replace power supply on legacy silent pc
I did a few PSU fan swaps before. Here is what I recommend:
1. open the PSU and remove the old fan - and simply cut the cables
2. buy non-PWM fan
3. power it from molex connector @5V - using red and black wires
4. mount the fan OUTSIDE the psu case using rubber mounts
*2 - I would buy a slower rated (like 800 rpm) fan if top PSU is not your only exhaust
*3 - 5V should be more than enough, but if it's not you can always wire it using yellow and red - that will result in 7V
*4 - "outside" - I mean the same place as the original fan, using the same mounting points - but placing the fan on the other side (outside) of the PSU case. Usually there is enough space to do this, and (at least in my case) this results in better noise characteristics, because there is a little more space between the fan and psu components/radiators.
----
I know your case has top psu - but for the cases with bottom psu (like mine) I'm always flipping the PSU so the fan is directed towards the case interior (and not the bottom intake) and I'm changing the fan direction to blow the air INSIDE the case. This serves as the bottom case intake with relatively cool air - so 1 less fan to deal with and psu always gets the cool air.
1. open the PSU and remove the old fan - and simply cut the cables
2. buy non-PWM fan
3. power it from molex connector @5V - using red and black wires
4. mount the fan OUTSIDE the psu case using rubber mounts
*2 - I would buy a slower rated (like 800 rpm) fan if top PSU is not your only exhaust
*3 - 5V should be more than enough, but if it's not you can always wire it using yellow and red - that will result in 7V
*4 - "outside" - I mean the same place as the original fan, using the same mounting points - but placing the fan on the other side (outside) of the PSU case. Usually there is enough space to do this, and (at least in my case) this results in better noise characteristics, because there is a little more space between the fan and psu components/radiators.
----
I know your case has top psu - but for the cases with bottom psu (like mine) I'm always flipping the PSU so the fan is directed towards the case interior (and not the bottom intake) and I'm changing the fan direction to blow the air INSIDE the case. This serves as the bottom case intake with relatively cool air - so 1 less fan to deal with and psu always gets the cool air.
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Re: need to replace power supply on legacy silent pc
ginahoy wrote:Thanks for the tips. I didn't even think about replacing just the fan. Of course!
The Arctic F12 is a PWM fan, right?
Not exactly: it's sold with either DC or PWM control.
ginahoy wrote:Does my power supply require PWM?
Absolutely no.
That's fine, but given the sleeve bearing how the PSU is oriented (fan facing upwards or downwards) really matter, reliability wise.ginahoy wrote:If not, I have a spare Scythe SY1225SC12M (KAZE-JYUNI) that I could install. It was reviewed strongly on this site and has very low starting voltage (2.4V, see http://bit.ly/2kW2UGh).
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Re: need to replace power supply on legacy silent pc
VERiON wrote:1. open the PSU and remove the old fan - and simply cut the cables
Absolutely no: the Seasonic fans just pop off.
VERiON wrote:*4 - "outside" - I mean the same place as the original fan, using the same mounting points - but placing the fan on the other side (outside) of the PSU case. Usually there is enough space to do this, and (at least in my case) this results in better noise characteristics, because there is a little more space between the fan and psu components/radiators.
But you go to overheat the PSU, so (detriment of some internal parts): in PSUs overhung fans do need to stay where they are.
Re: need to replace power supply on legacy silent pc
Can you elaborate more why is that? I was doing it with every (old/cheap) PSU I had with great effect (silence) - but maybe I was wrong all the time (and it won't be the first time in my life ).quest_for_silence wrote: But you go to overheat the PSU, so (detriment of some internal parts): in PSUs overhung fans do need to stay where they are.
Re: need to replace power supply on legacy silent pc
The hardest part about a fan swap is finding a decent replacement fan.
- probably ought to go with ball bearing fan given the usual horizontal placement...then again how long do you plan to keep this PSU?
- if you have this version of the S12 330, then you need a fan with a starting voltage of 4.3V or less.
- a helpful little guide on dealing with 3 pin fan connectors and 2 pin-fan sockets...
- probably ought to go with ball bearing fan given the usual horizontal placement...then again how long do you plan to keep this PSU?
- if you have this version of the S12 330, then you need a fan with a starting voltage of 4.3V or less.
- a helpful little guide on dealing with 3 pin fan connectors and 2 pin-fan sockets...
Re: need to replace power supply on legacy silent pc
any ball bearing 120mm fan recommendation? hopefully a budget-friendly one?
Re: need to replace power supply on legacy silent pc
Back in 2007-2008 I replaced noisy ball bearing Adda fans with Noctua NF-P12 in two different new PSU.
One connected to the PSU, the other one to outside running at 700 rpm. They are still in use by relatives.
Noctua has 6 years warranty, even then horizontally mounted. Not budget friendly though.
One connected to the PSU, the other one to outside running at 700 rpm. They are still in use by relatives.
Noctua has 6 years warranty, even then horizontally mounted. Not budget friendly though.
Provided you can remove the fan grill I doubt that a couple of cm will make any difference...quest_for_silence wrote:But you go to overheat the PSU...
Re: need to replace power supply on legacy silent pc
My system typically operates at <100W, with peak @ 155W.SebRad wrote:As you're not pushing the PSU with your system you should be fine using lower than original rpm fan.
The side of the Hyper6+ cooler is only 20mm from PSU fan. And even if I found one that would fit, the cooler would block almost half the fan face.VERiON wrote:mount the fan OUTSIDE the psu case using rubber mounts
Thanks. I forgot about orientation (re: sleeve fans). I can pick up the Arctic F12 suggested by Seb for about $8.CA_Steve wrote:probably ought to go with ball bearing fan given the usual horizontal placement
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Re: need to replace power supply on legacy silent pc
VERiON wrote:Can you elaborate more why is that? I was doing it with every (old/cheap) PSU I had with great effect (silence) - but maybe I was wrong all the time (and it won't be the first time in my life ).quest_for_silence wrote: But you go to overheat the PSU, so (detriment of some internal parts): in PSUs overhung fans do need to stay where they are.
As LongJan said elsewhere, it's advisable to remove the fan grill at first, because that limits the flow, creates some back pressure and requires some static pressure (to the fan).
Said that, any fan has (more or less) appreciable side leaks, and that reduces noticeably the actual flow at a distance, particularly whether the fan is out of the box which contains the devices to cool.
As a matter of fact (have a look for instance to the M12-II 430W), lots of PSU fan sports clear plastic baffles in order to limits the side leaks and somehow focus the flow where it should go (according to the PSU designer).
Last but maybe not least the airflow coming from a fan is not sort of a "cylindric column", but it's sort of a cone, so that the distance always matters.
How much does that matter? Well, I can't give you a precise answer but it does matter in the long run and, with reference to the OP scenario, that PSU already done a long run (so the effect is expected to be greater/faster, reliability-wise).
VERiON wrote:any ball bearing 120mm fan recommendation? hopefully a budget-friendly one?
Scythe KAZE-JYUNI DB (SY1225DB12M or SY1225DB12H offers a compatible start up voltage for the OP case).
Well, perhaps you may put your CPU fan a couple of cm away from your CPU heatsink and then tell me whether the temps are the same or not: is that difference crucial? I guess your mileage may vary (depending of the specific case).LongJan wrote:Provided you can remove the fan grill I doubt that a couple of cm will make any difference...quest_for_silence wrote:But you go to overheat the PSU...
Not to mention that often the thermistor used to control the fan could appreciably suffer of that inferior cooling, speeding up the fan itself.
Re: need to replace power supply on legacy silent pc
I don't have to try thatquest_for_silence wrote: Well, perhaps you may put your CPU fan a couple of cm away from your CPU heatsink and then tell me whether the temps are the same or not
Can tell you directly that if air has to choose between tightly spaced fins and an open gap, much of it will take the easy path and sneak through the gaps.
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Re: need to replace power supply on legacy silent pc
LongJan wrote:Can tell you directly that if air has to choose between...
That's about the same for the PSU...
Re: need to replace power supply on legacy silent pc
I wouldn't be surprised if finding a suitable fan for a swap is easier than finding a suitable replacement PSU.
New PSUs just don't cater well to the needs of legacy computers:
New PSUs just don't cater well to the needs of legacy computers:
- 20-pin motherboard connector? (Adapters are available, but bulky and awkward.)
- Emphasis on 3.3V and 5V currents to feed the CPU? (A higher power new PSU can provide sufficient on the lower voltages.)
- -5V line? (Totally missing on new PSUs, but is also rarely required.)
- Sufficient amount of Molex connectors? (Adapters are available but less than ideal.)
Re: need to replace power supply on legacy silent pc
To me this seems like a disaster waiting to happen.VERiON wrote:I did a few PSU fan swaps before. Here is what I recommend:
...
*2 - I would buy a slower rated (like 800 rpm) fan if top PSU is not your only exhaust
3. power it from molex connector @5V - using red and black wires
4. mount the fan OUTSIDE the psu case using rubber mounts
- First you suggest replacing a >2,000 rpm fan with an 800 rpm rated, cutting the available airflow by half or more.
- Then you suggest reducing those 800 rpm to ~300 rpm by reducing the available voltage, reducing the cooling capacity even further.
- The final nail in the coffin is to move the fan away from the cooling fins and placing it behind a fan grill, reducing the percentage of generated airflow touching the components.
The suggested mod might work, provided that:
- The typical power use is <25% of what the PSU is designed to deliver, and
- The intake air stays cool.
Re: need to replace power supply on legacy silent pc
I see that I didn't post a followup so hopefully I can put an end to this chatter about redesigning the PSU cooling system...
First, as I commented earlier, even if I wanted to, I don't have space to mount a PSU fan on the outside. Fortunately, the interference from the CPU cooler only affects the aft 3/4" of the fan. The bulk of the airflow is unrestricted.
Nor would I even consider reducing the fan's voltage. I do like outside-the-box thinking (literally in this case), but VERiON's strategy is a path too far for my taste
Turns out the spare fan in my closet was a Scythe SFF21E, which has fluid dynamic bearing (FDB). It's rated at 1200 CFM so it should be fine given my system's modest power consumption. It's definitely quieter than the stock fan. I keep my office at about 69F in the winter. Before it gets hot again, I plan to take some temperature measurements inside the PSU with a calibrated probe. I may come back to ask about recommended probe placement and temperature threshold.
@Olle, the power supply recommended by Neil near the top of this thread (SS-300ET) has the 20-pin connector my mobo requires, should I need to replace mine. Yeah, 8 years isn't so old
You guys are great. Just visiting this site again has got me thinking about building a new PC this summer. I'm sure I'll be back for your sage advice!!
First, as I commented earlier, even if I wanted to, I don't have space to mount a PSU fan on the outside. Fortunately, the interference from the CPU cooler only affects the aft 3/4" of the fan. The bulk of the airflow is unrestricted.
Nor would I even consider reducing the fan's voltage. I do like outside-the-box thinking (literally in this case), but VERiON's strategy is a path too far for my taste
Turns out the spare fan in my closet was a Scythe SFF21E, which has fluid dynamic bearing (FDB). It's rated at 1200 CFM so it should be fine given my system's modest power consumption. It's definitely quieter than the stock fan. I keep my office at about 69F in the winter. Before it gets hot again, I plan to take some temperature measurements inside the PSU with a calibrated probe. I may come back to ask about recommended probe placement and temperature threshold.
@Olle, the power supply recommended by Neil near the top of this thread (SS-300ET) has the 20-pin connector my mobo requires, should I need to replace mine. Yeah, 8 years isn't so old
You guys are great. Just visiting this site again has got me thinking about building a new PC this summer. I'm sure I'll be back for your sage advice!!
Re: need to replace power supply on legacy silent pc
1200 RPM 49.0 CFMginahoy wrote:Turns out the spare fan in my closet was a Scythe SFF21E, which has fluid dynamic bearing (FDB). It's rated at 1200 CFM so it should be fine given my system's modest power consumption.
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Re: need to replace power supply on legacy silent pc
ginahoy wrote:Turns out the spare fan in my closet was a Scythe SFF21E, which has fluid dynamic bearing (FDB). It's rated at 1200 CFM so it should be fine given my system's modest power consumption. It's definitely quieter than the stock fan. I keep my office at about 69F in the winter. Before it gets hot again, I plan to take some temperature measurements inside the PSU with a calibrated probe. I may come back to ask about recommended probe placement and temperature threshold.
I guess you need a thermal camera (check a detailled PSU review like those on THG or TPU made by crmaris).
Then, if you're satisfied, bring some bottles of your favourite beverage to cheers SPCR!ginahoy wrote:You guys are great. Just visiting this site again has got me thinking about building a new PC this summer. I'm sure I'll be back for your sage advice!!
Re: need to replace power supply on legacy silent pc
Seriously?! Those images were taken with a $3,000 FLIR E4 320x240!quest_for_silence wrote:I guess you need a thermal camera (check a detailled PSU review like those on THG or TPU made by crmaris).
my remote probe instrument has quick response so I can determine hottest location experimentally. And if I can get good contact, it should provide similar accuracy as a quality IR camera.
According to the caption for the IR image with 47C hot spot, "temperatures inside the PSU remain low". So would a peak of, say, 50 or 55C be considered acceptable?
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Re: need to replace power supply on legacy silent pc
ginahoy wrote:Seriously?!quest_for_silence wrote:I guess you need a thermal camera (check a detailled PSU review like those on THG or TPU made by crmaris).
Seriously: how can you assess the cooling prowess point-by-point?
I'd add that if a talented engineer like Artistides relies upon a thermal camera instead of a thermal probe, there's a chance that's the way to do.
Said differently, how can you know which are the critical points or areas without being the PSU designer? My question is not rhetorical.
ginahoy wrote:According to the caption for the IR image with 47C hot spot, "temperatures inside the PSU remain low". So would a peak of, say, 50 or 55C be considered acceptable?
Sorry, I can't help!
OTOH I wouldn't concern about that, heat is the bane of any electronics, so you're surely shortening the PSU life with such a fan swap: it's just a trade off, quietness vs long term reliability.
Re: need to replace power supply on legacy silent pc
OTOH it's a pretty old PSU, anyway. Go for the fan swap with the closet Scythe and see how it goes. My only concern is the replacement has a starting voltage of 4.8V and the OEM fan is 4.3V...so it may start up at a higher PSU temp....
Re: need to replace power supply on legacy silent pc
I may not be a PSU designer but I do know a fair amount about measurement and instrumentation (I have managed calibration and procedures for an environmental test instrument manufacturer). There are advantages of using a thermal camera for sure, but for my purposes it makes zero sense to spend $3k to measure something I can already measure 'well enough' with an instrument I already own.quest_for_silence wrote:I'd add that if a talented engineer like Artistides relies upon a thermal camera instead of a thermal probe, there's a chance that's the way to do.
Actually, that's an entirely different issue. Even a $3k camera doesn't tell us which are the critical points. I guess I could hire a PSU designer assist in the analysisSaid differently, how can you know which are the critical points or areas without being the PSU designer? My question is not rhetorical.
I'm totally unconcerned about the long term life expectancy of an 8-yr-old PSU. I just want to make sure the 1200 RPM fan isn't cooking the components.OTOH I wouldn't concern about that, heat is the bane of any electronics, so you're surely shortening the PSU life with such a fan swap: it's just a trade off, quietness vs long term reliability.
Changing the subject a bit, Speedfan reports all the system voltages. I wonder how useful V levels might be as indicators of a failing PSU?
Re: need to replace power supply on legacy silent pc
Thanks. With system on idle (~75W), the Scythe is running, so starting voltage isn't an issue.CA_Steve wrote:My only concern is the replacement has a starting voltage of 4.8V and the OEM fan is 4.3V...so it may start up at a higher PSU temp....
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Re: need to replace power supply on legacy silent pc
ginahoy wrote:I may not be a PSU designer but I do know a fair amount about measurement and instrumentation (I have managed calibration and procedures for an environmental test instrument manufacturer).quest_for_silence wrote:I'd add that if a talented engineer like Artistides relies upon a thermal camera instead of a thermal probe, there's a chance that's the way to do.
So what, gina? I didn't implied you were untalented or illitterate, I just say you may not know what/where to measure.
You know, those questions like "How many point?". Two? Three? More? Where should they be located? On primary? On PFC? O secondary mosfets? On the heatsinks? Which heatsink? What do they mean?
OTOH if you know, then I'll stand corrected: in any case do what you think best, I just said that's a waste of time/energies.
ginahoy wrote:There are advantages of using a thermal camera for sure, but for my purposes it makes zero sense to spend $3k to measure something I can already measure 'well enough' with an instrument I already own.
I didn't suggested to buy a FLIR for a fan swap on a too old PSU: if you understood so, sorry, it's just a language barrier.
Said differently: I'm not stupid.
ginahoy wrote:Actually, that's an entirely different issue. Even a $3k camera doesn't tell us which are the critical points. I guess I could hire a PSU designer assist in the analysisSaid differently, how can you know which are the critical points or areas without being the PSU designer? My question is not rhetorical.
Nice tease, but pointless.
ginahoy wrote:I'm totally unconcerned about the long term life expectancy of an 8-yr-old PSU. I just want to make sure the 1200 RPM fan isn't cooking the components.OTOH I wouldn't concern about that, heat is the bane of any electronics, so you're surely shortening the PSU life with such a fan swap: it's just a trade off, quietness vs long term reliability.
What's the difference?
BTW, you don't cook anything, a fan swap is not an owen.
They are absolutely not useful: any sw/bios reading is TOTALLY unreliable/useless.ginahoy wrote:Changing the subject a bit, Speedfan reports all the system voltages. I wonder how useful V levels might be as indicators of a failing PSU?
Re: need to replace power supply on legacy silent pc
Cool beans.ginahoy wrote:Thanks. With system on idle (~75W), the Scythe is running, so starting voltage isn't an issue.CA_Steve wrote:My only concern is the replacement has a starting voltage of 4.8V and the OEM fan is 4.3V...so it may start up at a higher PSU temp....