Strange PowerStream 600 problem...

[AlterBridge86]

Hey guys - I replaced my DFI Ultra-D with a eXpert recently and since then i've had a very strange issue. It seems that whenever I turn off the computer, i can not turn it back on without completely switching the PSU off or unplugging it, waiting 5 seconds, then powering up again. I contacted DFI Tech Support and they sent a message off to DFI HQ in Taiwan who worked on the problem. This is the summary email they sent me..



Hi Frank,

About PSU Issue . FYR

We discovered a phenomenon when DFI LanParty and Infinity M/B Series attached with a specific brand of PSU (Power Supply Unit), system will shutdown automatically two seconds after it was switched on. According to our analysis, This phenomenon is now categorized as PSU’s spec. incompatible issue.
Here we provide our test and analysis report of LP NF4 M/B series、 NF4 Infinity M/B Series、LP UT NF4 SLI-DR Expert and LP UT RDX200 CF-DR with Seasonic S12-600W, S12-500W and Antec Neo HE500 PSU below:

1.
Test Environments:
M/B was only attached with CPU, PCI-E Graphic Card & RAM module.
Summary:
After reboot, the loading of +12v(1)and 12v(2) are relatively too low, approximately only about 0.2A, this type of low current will activate PSU’s minimum loading protection, which will cause M/B shutdown automatically.
(Illustrated on the attached photo: config1 (NG).jpg.)

2.
Test Environments:
M/B was only attached with CPU, PCI-E VGA Card & RAM module, and when PSU is attached with a 1Amp of dummy load.
Summary:
Because the voltage of +12V (2) reaches the minimum loading, system boot up normally. (Illustrated on the attached photo:config3(OK).jpg.)

p.s.: The min. loading of PSU’s +12v1 and +12v2 is 1Amp each, with the total of 2Amp.

Analysis:
The result of tests obviously indicates, this M/B shutdown phenomenon was caused by the minimum loading protect of PSU +12V set too high(2A). System actually does not need this kind of high min. loading voltage, so the PSU’s minimum loading protection will be activated and lead to the consequence of M/B automatically shutdown. In general speaking, the min. loading spec. of PSU 12V(2) is not suitable for the usage on M/B. The suggestion of changing PSU will eliminate this phenomenon. If end users have further enquiries, the collection of end users’ equipments will be needed for further technical analysis.

Best,
Kent

Now, i've also seen many other people around this forum and DFI-Street who have the 600W powerstream and aren't experiencing any such problem, so i'm wondering if we could go ahead and try to replace this PSU and see if that helps? Thanks in advance. :)

-Frank

[RyderOCZ]

Hello,

The PSU worked fine with the Ultra-D right? Why would switching motherboards make the PSU be bad?

[AlterBridge86]

Good question - and i was wondering the same thing myself...either way, I have a modstream coming tuesday for a HTPC i'm building so i'll throw it in my box and see if it solves the problem - i'll let you know ASAP.

[AlterBridge86]

Sorry for the huge delay - was busy and then i completely forgot about the thread. Either way, I did try it out with the modstream I got for another computer and sure enough, the problem persisted. So now i have to call DFI and convince them that it indeed IS the boards fault and that it needs to be RMA'd. Thanks for the help! :toast:

[formyfaith]

Sorry for the huge delay - was busy and then i completely forgot about the thread. Either way, I did try it out with the modstream I got for another computer and sure enough, the problem persisted. So now i have to call DFI and convince them that it indeed IS the boards fault and that it needs to be RMA'd. Thanks for the help! :toast:

Just saw this thread.

AFAIK the expert mobo you have is faulty, and it indeed needs an RMA service.

There were 130 expert mobos imported through the dealer I know overhere, and about 6-7 among them had that specific prob. It's not the PSU's problem for sure. So those were all RMAed. ;)

[AlterBridge86]

good to know ForMyFaith - thanks a lot!:toast: