Seasonic X-1250 - How Many 12v Rails.

[UaVaj]

was reading some reviews on newegg then on ocn, and it mention dishonest specs by seasonic. that seasonic x-1250 is actually a 4 rails with 30/30/45/45 amp on each of the 12v rails. unable to find such evidence on johnny's x-1250 review.

hard's x-1250 review suggests 4 rails.
johnny's xfx 1250 review proves to be 4 rails.



currently own the seasonic x-1250. concern that 290x x3 or 290x x4 may overdraw one of its 12v rails "if" indeed is 4 rails.


Moved from C&C to PSUs by request of OP
-ViRGE

 

[OVerLoRDI]

Just doing some basic math. 290x are ~300W cards, so 4 of those = 1200W. Once you tack on CPU and storage, you are way over the 1250 watt max of the unit. For a unit like this, I'd recommend a 1500W PSU or multiple PSUs, especially if you want to do any overclocking.

Also you should watercool those 290Xs, otherwise the heat/noise is going to be ridiculous.

 

[Tweakin]

This should be posted in the Power Supplies Forum.

 

[Maximilian]

I remember reading this, its actually 4 rails but they did it in a way that they can market it as single rail for the boneheads that think one all powerful rail to rule them all is better.

Cant remember the specifics of it though.

 

[UaVaj]

for the enthusiasts who understands psu. at this level of wattage - multiple rails is a safer design. just requires a little bit of proper planning when connecting stuff.

if indeed is 4 rails. just need solid documentations showing which connectors is connected to which rails so the wattage draw can be spread more efficiently among all the rails.

 

[ethebubbeth]

HardOCP was unable to use a 1350W PSU with an overclocked 3930k and crossfire 295X2, which is essentially 290X quadfire. 1250W would definitely be insufficient.

"With the combined wattage measured at the wall with our power meter we were pulling 1400W with dual AMD Radeon R9 295X2 CrossFire and the rest of the system."

 

[UaVaj]

no intention of 290x overclocking so 1250w should be sufficient. per hardocp shows each stock 290x pulls ~255w. that is 1020w for 4. still 230w left for cpu, ssd, fan and etc.

more concern about exceeding and engaging the over current protection.

 

[lehtv]

no intention of 290x overclocking so 1250w should be sufficient. per hardocp shows each stock 290x pulls ~255w. that is 1020w for 4. still 230w left for cpu, ssd, fan and etc.

more concern about exceeding and engaging the over current protection.

So you intend to run the unit at 90% load? Not a good idea for the long term.

 

[UaVaj]

thanks for the concern.

unit has 4 years left on the warranty. so as long as it does not burn down the house. 90% load is plenty fine. seasonic is a top quality psu.

plus not like it will be running 90% load 24/7. more like 5-6 hours per week only when gaming. most of the time it will be idling when web surfing, or the like.

 

[BFG10K]

I can concur that some Seasonic units have "hidden" multi-rails, despite what the label says. A conversation I had with their tech staff resulted in me being informed that my X560 actually has two rails, though they wouldn't give me a straight answer as to how the distribution was arranged.

I guess Antec's videos with a Seasonic PSUs causing smoke did the trick. I personally prefer multi-rail myself, even for small units. Multi-rail OCP is generally much faster at tripping than OPP is, and therefore safer by extension.

As for the OP's questions, there's no issue running @ 90% load. The quality units are rated for 100% load @ 50C (i.e. the manufacturer guarantees this as continuous output).

Rail distribution won't be an issue either. If you're tripping OCP then your PSU's total wattage is too low to begin with.

 

[UaVaj]

issue is not overall load. know for sure 1250w is enough for this configuration.
just want to assure the load is spread evenly as best as possible across all 4 rails.

according to johnny breakdown of the 12v rail distribution and hardocp regurgitating it.
looks like converting the molex for the one of the 290x may be necessary.

 

[BFG10K]

issue is not overall load. know for sure 1250w is enough for this configuration.
just want to assure the load is spread evenly as best as possible across all 4 rails.

Again, unless you do something silly like daisy-chain everything off one cable, the distribution doesn't matter. Just plug things in the most logical places.

The OCP trip points will probably be at the level required to stop the wire or connectors burning, so they should never trip under normal use.