I'm looking for a more silent replacement of an Enpower ENP8345L-OVT, which powers a 16-core Xeon-D server that pulls about 8W off (BMC powered exclusively through +5Vsb), 40W in idle and 80W under full load.
The power draw above 8W is exclusively through the +12V rail, using the 8-pin CPU connector.
My eye fell on a Pico PSU, more specifically the Wenjun Technology DC-ATX-200W Pico sourced from AliExpress.
It claims that it can do 15W on the +5Vsb and 180W on the +12V. That's more than enough for my needs.
Tested it with a Leicke ULL 12V 120W AC-DC brick, which is supposedly one of the more trustworthy brands for AC-DC bricks (the build quality is pretty solid if that counts for anything).
Results:
- BMC idles at 9W instead of 8W with Enpower. Truth be told the lower efficiency of the +5Vsb could also be partly or even fully be due to the 12V brick; I don't have any independent measurements for the 12V brick's efficiency.
- When I power on the server from the BMC interface, the cpu fan moves ever so slightly and then the BMC is reset. I never see a power spike on the power meter, so it seems that as soon as the 12V pull starts the +5Vsb drops below what's required for the BMC to keep running.
Some comments:
- I'll contact the seller and see what they have to say.
- My use case may be an outlier, as very few people would put as much on +5 Vsb and then pull the full wattage only through the 12V rail on the 8pin CPU connector; maybe the Wenjun expects the 12V draw to come primarily through the 24-pin ATX plug instead (the cables to the 12V 8-pin CPU plug are awfully thin, not rated for much wattage). On the other hand, I wouldn't expect there to be more than one 12V rail on this pico-style DC-DC converter, and therefor would expect the issue to be that it cannot keep +5Vsb stable once the load on 12V commences.
The power draw above 8W is exclusively through the +12V rail, using the 8-pin CPU connector.
My eye fell on a Pico PSU, more specifically the Wenjun Technology DC-ATX-200W Pico sourced from AliExpress.
It claims that it can do 15W on the +5Vsb and 180W on the +12V. That's more than enough for my needs.
Tested it with a Leicke ULL 12V 120W AC-DC brick, which is supposedly one of the more trustworthy brands for AC-DC bricks (the build quality is pretty solid if that counts for anything).
Results:
- BMC idles at 9W instead of 8W with Enpower. Truth be told the lower efficiency of the +5Vsb could also be partly or even fully be due to the 12V brick; I don't have any independent measurements for the 12V brick's efficiency.
- When I power on the server from the BMC interface, the cpu fan moves ever so slightly and then the BMC is reset. I never see a power spike on the power meter, so it seems that as soon as the 12V pull starts the +5Vsb drops below what's required for the BMC to keep running.
Some comments:
- I'll contact the seller and see what they have to say.
- My use case may be an outlier, as very few people would put as much on +5 Vsb and then pull the full wattage only through the 12V rail on the 8pin CPU connector; maybe the Wenjun expects the 12V draw to come primarily through the 24-pin ATX plug instead (the cables to the 12V 8-pin CPU plug are awfully thin, not rated for much wattage). On the other hand, I wouldn't expect there to be more than one 12V rail on this pico-style DC-DC converter, and therefor would expect the issue to be that it cannot keep +5Vsb stable once the load on 12V commences.
