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post #11 of 16
To put things in perspective, a 650W 80PLUS Platinum power supply needs to dissipate up to (650/0.89)-650 = ~80W of heat. That's like a whole Radeon HD6750. And unlike a graphics card where all of that heat is concentrated in one handy place, it's distributed throughout the unit, in the bridge rectifier, primary cap, PFC coil, switching transistors, transformer, rectifiers, and output caps. And many of those components cannot be directly heatsinked.
post #12 of 16
Thread Starter 
TYVM for the wisdom smile.gif

so given the topology of the current fanless units the super flower is still the preferred platform over seasonic? and enermax is simply being "generous" in their power rating? as overbuilt as these units are, i don't doubt any of these PSU's being able to pump out 650w but enermax is simply putting that on the sticker instead of holding it in reserve? I guess what i'm asking is are there technologies that may account for the varied wattage ratings while still accounting for efficiency and thermal load?

this might sound really stupid, but is there such thing as a solid/polymer cap for these sizes that can account for the claims enermax are making for a 650w unit? and would that account for the fairly substantial increase in rated wattage while still safely remain passive? I'm still trying to wrap my head around the large increase in rated power considering previous attempts have only yielded 500w units. in previous wattage jump, (from 400w to 500w passive) there was an increase in efficiency to partially account for the additional thermal load. however this time, the units are already platinum rating and the jump is quite substantial. this makes me wonder if there was a different technology involved to make it possible?

i mean afaik, relatively little have changed in PSU design and material in recent years. usage of higher quality components has allowed greater efficiency, but nothing i can think of that would account for a jump from a 500w class to a 650w class w/o a substantial thermal load increase. or are they simply banking on the fact that the silent computing crowd would never pull 650w from their rigs? or maybe they are just offering shorter warranty on an otherwise "lifetime quality" unit? biggrin.gif

I guess I need to wait for the enermax unit to get reviewed to see what they have up their sleeves. as for the reason to do this, i've wanted to get a passive PSU for a LONG time now (since the antec phantom days). I know it's completely pointless since PSU is usually one of the quietest part in a proper build, but it's something i've been wanting to do for a long time. it's one of those stubborn aesthetic choices that i've made so i feel good inside type of thing biggrin.gif it was the reason I bought an FT02 since i feel it is the most logical chassis if i was to build an entirely passive machine. (missed out on the zalman TNN500AF frown.gif but i feel good enough about the rotated mobo design of the FT02 to give it an attempt) CPU coolers are powerful enough these days that ivybridge/haswell can be passively cooled w/o much issues (delidded with better goop applied obviously) should be even easier when broadwell comes around and another TDP drop on that 14nm tech. GPU is coming along with passive 7850 although i may have to wait another die shrink since i've moved to 1600P resolution recently. it's been a decade long project that is finally starting to see possibilities with emerging technologies biggrin.gif
post #13 of 16
Quote:
Originally Posted by psyclum View Post

TYVM for the wisdom smile.gif

so given the topology of the current fanless units the super flower is still the preferred platform over seasonic? and enermax is simply being "generous" in their power rating? as overbuilt as these units are, i don't doubt any of these PSU's being able to pump out 650w but enermax is simply putting that on the sticker instead of holding it in reserve? I guess what i'm asking is are there technologies that may account for the varied wattage ratings while still accounting for efficiency and thermal load?

this might sound really stupid, but is there such thing as a solid/polymer cap for these sizes that can account for the claims enermax are making for a 650w unit? and would that account for the fairly substantial increase in rated wattage while still safely remain passive? I'm still trying to wrap my head around the large increase in rated power considering previous attempts have only yielded 500w units. in previous wattage jump, (from 400w to 500w passive) there was an increase in efficiency to partially account for the additional thermal load. however this time, the units are already platinum rating and the jump is quite substantial. this makes me wonder if there was a different technology involved to make it possible?

i mean afaik, relatively little have changed in PSU design and material in recent years. usage of higher quality components has allowed greater efficiency, but nothing i can think of that would account for a jump from a 500w class to a 650w class w/o a substantial thermal load increase. or are they simply banking on the fact that the silent computing crowd would never pull 650w from their rigs? or maybe they are just offering shorter warranty on an otherwise "lifetime quality" unit? biggrin.gif

I guess I need to wait for the enermax unit to get reviewed to see what they have up their sleeves. as for the reason to do this, i've wanted to get a passive PSU for a LONG time now (since the antec phantom days). I know it's completely pointless since PSU is usually one of the quietest part in a proper build, but it's something i've been wanting to do for a long time. it's one of those stubborn aesthetic choices that i've made so i feel good inside type of thing biggrin.gif it was the reason I bought an FT02 since i feel it is the most logical chassis if i was to build an entirely passive machine. (missed out on the zalman TNN500AF frown.gif but i feel good enough about the rotated mobo design of the FT02 to give it an attempt) CPU coolers are powerful enough these days that ivybridge/haswell can be passively cooled w/o much issues (delidded with better goop applied obviously) should be even easier when broadwell comes around and another TDP drop on that 14nm tech. GPU is coming along with passive 7850 although i may have to wait another die shrink since i've moved to 1600P resolution recently. it's been a decade long project that is finally starting to see possibilities with emerging technologies biggrin.gif


There is really noting technically stopping companies form making even a 1000W passive PSU if they wanted. It just requires them to use more expressive parts rated for higher wattages and more expensive heatsinks. The thing is that the the cost of making a higher power PSU does not scale linearly. Higher power parts get exponentially more expensive. Making a 1000W passive PSU would be really, really expensive. How expensive I don't know but my guess would be they could not sell it for less then $500.

So its not that they can't make high power passive PSU's but that there is not a market for them. Even now there is only a very small number of people that are willing to pay something like $150 for a 550W unit just for it to be platinum and passive.

I'm not sure what the price of the passive Enermax 650W PSU was but I think I heard it was around $250. So the reason why the Enermax PSU can put out 650W is due to it being a more expensive unit.
Edited by Bit_reaper - 8/1/13 at 9:59pm
    
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Hard DriveHard DriveHard DriveHard Drive
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Optical DriveCoolingOSMonitor
generic LG DVD WC'd , Supreme LT, NexXxoS Xtreme III 360, Phob... Windows 7 x64 Samsung 27" LED S27A550B 
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ACER 23" x233H Dell U3415W Logitech G11 Chieftec 850W 
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Phanteks enthoo luxe Razer deathAdder respawn steelseries Qck Yamaha HTR-6130 AV Receiver 
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post #14 of 16
Thread Starter 
actually if there was a way to make a passive 1kw PSU in an ATX form factor, i'd expect it to be MUCH more expensive. after all we are treading on NASA's weight/space requirements biggrin.gif my question is what IS the next step in PSU construction technology? i have no clue where to begin because I don't know what technology i'm even trying to google biggrin.gif
post #15 of 16
Quote:
Originally Posted by CM Phaedrus View Post

To put things in perspective, a 650W 80PLUS Platinum power supply needs to dissipate up to (650/0.89)-650 = ~80W of heat. That's like a whole Radeon HD6750. And unlike a graphics card where all of that heat is concentrated in one handy place, it's distributed throughout the unit, in the bridge rectifier, primary cap, PFC coil, switching transistors, transformer, rectifiers, and output caps. And many of those components cannot be directly heatsinked.

^^^ This.

Many of the components in a PSU are perfectly happy running at 80-105C without a problem, and passive cooling works just fine for them. Well said, Phaedrus.

Greg
post #16 of 16
Quote:
Originally Posted by psyclum View Post

actually if there was a way to make a passive 1kw PSU in an ATX form factor, i'd expect it to be MUCH more expensive. after all we are treading on NASA's weight/space requirements biggrin.gif my question is what IS the next step in PSU construction technology? i have no clue where to begin because I don't know what technology i'm even trying to google biggrin.gif

I don't think it would be that hard to make one. Take something like a Platimax 1500W as a base. Replace the casing with a milled out aluminium part with fins. Then use heat pipes to connect the hottest active parts to the outer casing thus leading most of the heat away form the other harder to cool passive parts. Have the top perforated for ventilation. I think that would already be in the ball park of an passive 1000W unit. If the PSU was still not running cool enough extend it to a similar size as a Rosewill Hercules 1600W and perhaps redesign the PCB so that the components are further apart from one another. Sure it would be larger the your average PSU but if Rosewill can sell the Hercules as an ATX power supply I don't think it would be unreasonable.
    
CPUMotherboardGraphicsRAM
i7 920 OC 4.0 GHz 1.35v HT on Asus P6T 1366 SLI Gigabyte GTX 970 OCZ 12GB DDR3 GOLD/Platinum mix 
Hard DriveHard DriveHard DriveHard Drive
Samsung Spinpoint F1 1TB Western digital 300GB Western digital Caviar Blue 1TB Samsung 840 EVO 250Gb 
Optical DriveCoolingOSMonitor
generic LG DVD WC'd , Supreme LT, NexXxoS Xtreme III 360, Phob... Windows 7 x64 Samsung 27" LED S27A550B 
MonitorMonitorKeyboardPower
ACER 23" x233H Dell U3415W Logitech G11 Chieftec 850W 
CaseMouseMouse PadAudio
Phanteks enthoo luxe Razer deathAdder respawn steelseries Qck Yamaha HTR-6130 AV Receiver 
AudioAudio
Yamaha NS-50B floor tower speakers miditech Audiolink II stereo sound card 
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CPUMotherboardGraphicsRAM
i7 920 OC 4.0 GHz 1.35v HT on Asus P6T 1366 SLI Gigabyte GTX 970 OCZ 12GB DDR3 GOLD/Platinum mix 
Hard DriveHard DriveHard DriveHard Drive
Samsung Spinpoint F1 1TB Western digital 300GB Western digital Caviar Blue 1TB Samsung 840 EVO 250Gb 
Optical DriveCoolingOSMonitor
generic LG DVD WC'd , Supreme LT, NexXxoS Xtreme III 360, Phob... Windows 7 x64 Samsung 27" LED S27A550B 
MonitorMonitorKeyboardPower
ACER 23" x233H Dell U3415W Logitech G11 Chieftec 850W 
CaseMouseMouse PadAudio
Phanteks enthoo luxe Razer deathAdder respawn steelseries Qck Yamaha HTR-6130 AV Receiver 
AudioAudio
Yamaha NS-50B floor tower speakers miditech Audiolink II stereo sound card 
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