Seasonic S1P-651FCPN5
The Seasonic S1P-651FCPN5 is a new unit they showed at Computex 2017. It is a semi-modular (!) 650W Platinum-rated 150mm FlexATX. It is due to release by the end of the year.
Load table
The Seasonic has a 30% higher max wattage than the previous SFF-favorite, the 500W FSP FSP500-50FSPT. Unlike the FSP however, there is just a single 12V rail that is rated for a max of 53A (636W).
500W was already enough though, so more importantly for consumer use is the presence of the -12V (negative) rail that the FSP lacks. The -12V is completely obsolete on modern hardware but despite that some motherboards won't POST without it anyway.
Fan
When I asked the product manager for this PSU, he said that the fan controller is temperature-based and does NOT spool up to full speed as part of the power supply's power on test procedure like the FSP (very annoyingly) does.
The fan on the display unit is a 40x20mm Jamicon KF0420 series, almost certainly the KF0420B1S in the 2-wire variant since the PM said the fan is dual ball bearing and it matches the 0.13A visible on the sticker.
Since the S1P-651FCPN5 is still in development it's not guaranteed this is the fan production units will use.However, changing the fan seems minor but it would require re-certification, so since it's supposed to release by the end of the year I think it's reasonable to assume it'll be the same.
Edit: After inquiring with Seasonic about if they had any noise specs of temperature/RPM curves yet, they informed me that the production unit will likely use the Sanyo Denki (Seasonic's preferred fan vendor when reliability is criticial) 9GA0412P6G001:
So at 16,000 RPM this isn't looking too good for noise levels at max load, though there's still hope for relatively quiet operation at loads a typical SFF build would see.
Cables
The S1P-651FCPN5 (or at least the demo unit at Computex) is semi-modular. The way it's implemented isn't anything special but it's better than nothing. The only sticking point is that the harness shown here only has 3x 12V wires which isn't really enough for both the CPU and PCIe connectors with a decently beefy rig.
I'd assume the harness could be modified but I have no idea what the MOQ is for that.
Unlike many of the other FlexATX units I saw at Computex, since this is Seasonic there's a decent chance these will be available such that mere mortals can buy them.
I'll be sure to update this thread as new information comes in.
The Seasonic S1P-651FCPN5 is a new unit they showed at Computex 2017. It is a semi-modular (!) 650W Platinum-rated 150mm FlexATX. It is due to release by the end of the year.
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Specifications
- Dimensions: 150mm x 81.5mm x 40.5mm (L x W x D)
- Rated wattage: 650W
- Efficiency: 80 PLUS Platinum
- Rails: +3.3V 20A | +5V 20A | +12V 53A | -12V 0.3A | +5Vsb 3A
- Fan: 40mm x 20mm
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Load table
The Seasonic has a 30% higher max wattage than the previous SFF-favorite, the 500W FSP FSP500-50FSPT. Unlike the FSP however, there is just a single 12V rail that is rated for a max of 53A (636W).
500W was already enough though, so more importantly for consumer use is the presence of the -12V (negative) rail that the FSP lacks. The -12V is completely obsolete on modern hardware but despite that some motherboards won't POST without it anyway.
---------------------------
Fan
When I asked the product manager for this PSU, he said that the fan controller is temperature-based and does NOT spool up to full speed as part of the power supply's power on test procedure like the FSP (very annoyingly) does.
The fan on the display unit is a 40x20mm Jamicon KF0420 series, almost certainly the KF0420B1S in the 2-wire variant since the PM said the fan is dual ball bearing and it matches the 0.13A visible on the sticker.
Since the S1P-651FCPN5 is still in development it's not guaranteed this is the fan production units will use.
Edit: After inquiring with Seasonic about if they had any noise specs of temperature/RPM curves yet, they informed me that the production unit will likely use the Sanyo Denki (Seasonic's preferred fan vendor when reliability is criticial) 9GA0412P6G001:
So at 16,000 RPM this isn't looking too good for noise levels at max load, though there's still hope for relatively quiet operation at loads a typical SFF build would see.
Despite being a ball-bearing the fan in the FSP 500W is surprisingly acceptable in regards to noise at loads up to about 150W. At 300W load on the FSP I was seeing 8600 RPM and at full load the fan was going full speed at 13k.
The fan in the Seasonic here by comparison maxes out at 8500 RPM, which combined with the temperature-based controller will hopefully mean a relatively quiet fan curve for the wattages most SFF builds will see.
Regardless, this wouldn't be SFF Forum if we didn't try to improve things, and luckily the fan is 20mm thick so there are some potential fan swap options to avoid that grinding noise inherent to ball bearings:
Let me know if any of you find other options. Avoid just plain sleeve bearings though because at these RPMs they'll fail quickly. Also fan manufacturer specs are definitely better in the industrial side of things, but still suspect. Tread with caution.
The fan in the Seasonic here by comparison maxes out at 8500 RPM, which combined with the temperature-based controller will hopefully mean a relatively quiet fan curve for the wattages most SFF builds will see.
Regardless, this wouldn't be SFF Forum if we didn't try to improve things, and luckily the fan is 20mm thick so there are some potential fan swap options to avoid that grinding noise inherent to ball bearings:
- ebm-papst 412 H: Sintec bearings, 8100 RPM, 7.95 CFM, 29 dBA
- Sunon MF40201VX-1000U-A99 (pg 32): VAPO bearings, 8000 RPM, 10.8 CFM, 27.5 dBA
Let me know if any of you find other options. Avoid just plain sleeve bearings though because at these RPMs they'll fail quickly. Also fan manufacturer specs are definitely better in the industrial side of things, but still suspect. Tread with caution.
---------------------------
Cables
The S1P-651FCPN5 (or at least the demo unit at Computex) is semi-modular. The way it's implemented isn't anything special but it's better than nothing. The only sticking point is that the harness shown here only has 3x 12V wires which isn't really enough for both the CPU and PCIe connectors with a decently beefy rig.
I'd assume the harness could be modified but I have no idea what the MOQ is for that.
---------------------------
Unlike many of the other FlexATX units I saw at Computex, since this is Seasonic there's a decent chance these will be available such that mere mortals can buy them.
I'll be sure to update this thread as new information comes in.
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