NF4 Expert will not cold boot- psu issue?

[red930]

Jeez dude!

 

I never said "switch bounce" is the only factor involved. Please read and understand the first post in this thread.

 

Every bit of information I have is available there.

 

I'm done with this!

END OF LINE

I don't think the switch bounce is the only factor causing the cold boot problem. Like I've said many times, I have the cold boot problem only when overclocked with two video cards. Also, reseting the 5vsb by power cycling the PSU allows the machine to cold boot without any "switch bounce". It seems to be an interaction between switch bounce and high current draw (out of spec with ATX standard recommendations by the way) on the 5v standby rail.

 

I really think we are talking about different combinations of the same problem... not two distinct problems as you have summarized them.

 

 

I just want to post my observations for other people's benefit. If you really agree with me that it doesn't make a difference who is at fault, stop blaming the PSU manufacturers. Its as simple as that.

 

 

Any chance we can see your experiment (just results and method including EVERY component in each system tested)?

[frenchie]

I never said "switch bounce" is the only factor involved. Please read and understand the first post in this thread.

You asked me to find where you had said the motherboard was the problem in the very first post in this thread regarding "switch bounce". I assumed you were making a distinction between the switch bounce problem and the current draw problem. Sorry, if I misunderstood. I think I was confused because you seem to sometimes be arguing that the MB plays no role in the switch bounce problem:

 

Once again, "switch bounce" is a problem related to the PSU. Adding the capacitor smooths the voltage spikes and allows the PSU to sense a normal start.

You state that the Expert is OUT OF SPEC here and then go on to say that it is a PSU problem:

 

The Expert board can draw more than the rated 2.0Amps on the 5VSB line. But! If the Expert board was the only point of failure, no power supply would run it properly.

 

I'm done too. I don't feel that you approaching this issue logically and you seem very defensive about it long before I stepped in.

 

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To everyone else, please post your results. I am curious how often the cap mod fixes this problem. And above all, don't mod your PSU or MB... mod your switch (or just plug the cap leads into the MB power on plug w/o soldering).

 

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PS - Let me be clear about one thing: The Expert still rocks the ASUS even with its little quirks. I gave the ASUS to my girlfriend.

[xtremeph]

has anyone who has done this "cap mod" taken a picture of how it is done?

[frenchie]

This is a photo of an example of how i did it. Its covered with heatshrink now and I don't feel like cutting it out. Its pretty straightforward though. I have an extension cable on the power switch and I just plugged the cap leads into the connector along with the extension. The end that says "H.D.D. Led" will get plugged into the motherboard ATX power header (Its an LED extension cable I am using as a power switch extension cable):

 

 

Just make sure the cap leads dont cross. I taped them down with electrical tape and then covered the whole thing with heatshrink.

[Atoth]

Big surprise, my OCZ 520w SLi PSU died on me yet again today... I can't tell if it's the mobo causing the failure in the PSU unit or if it's just the PSU itself failing. Both brand new 520w SLI failed within the same 3 month period of being installed on the board. Both DFI and OCZ seem to be very flakey on the issue while the end user gets stuck with the bill and downtime. If the eXpert is drawing too much power and always causing this overloaded state on bootup, which causes the cold bug, wouldn't this cause the PSU to fail quicker?

 

So can anyone recommend a PSU that actually works and supplies the proper amperage to the eXpert on boot? I was thinking the PC Power & Cooling 510w, but if other people are having the same issue on that PSU what's really the point? I'm getting really sick and tired of having to replace my PSU every 3 months and it's getting pretty damned expensive. Do I just bite my nails and RMA this supposed "eXpert" board back to DFI? I tell you I was happy as pie when I built my system and I still love it, but this is getting out of control... :confused:

[volcnnxn]

hello everybody, i know alot are frustrated with the cold boot problem wit h the ocz powerstream and dfi expert. i also was suffering from this problem , i talked to ocz and rma'd my powerstream 520 with the new ocz gamextreme model (600). This has resolved my issue, i have not had a single cold boot problem. ocz was very helpful and recieved my power supply in 4 days. Its not worth the trouble , just switch it out and move on. i just wanted to let you guys know. thanks

[Wolf Frost]

I was having the cold boot issue, or I should say that I can replicate the cold boot issue.

 

I had dual prime95 running and was monitoring my temps on MBM when I noticed that the 5v rail fell below 5.0. I, then, closed dual prime95 and the 5v rail bounced back to exactly 5.0. I was thinking that I should increase the 5v a little since I could do it with ease with the PowerStream. I increased it to exactly, as indicated in MBM, to 5.02. After doing this, I started to have sporadic cold boot issues. My configuration stayed the same with no changes, except for the increase to the 5v rail. Knowing this, I reduced the 5v rail back to exactly 5.0 and the cold boot issues went away. No more cold boot issues at all. To be sure, my 5v falls below 5.0 during load but the lights are all green on the psu.

 

I don't know if this is the cause, but increasing/decreasing the 5v helped me create the cold boot issues and helped me made it disappear, respectively. This info might help, maybe it won't, but it's worth a try if those of you haven't tried it yet.

[dfi_user]

My problem with expert is, when i do proper shutdown, and then power on the pc, it works fine. but if i shutdown pc during post, then i press the on button again, the pc wont on. why? izzit the problem same as what u all faced?

[MidnightUT]

My problem with expert is, when i do proper shutdown, and then power on the pc, it works fine. but if i shutdown pc during post, then i press the on button again, the pc wont on. why? izzit the problem same as what u all faced?

 

Yes that is similar to what I am experiencing. So long as it is shut down normally I can do the "quick tap" method to reboot it. However if I shut it down during post it is dead as dead can be until I turn off the rocker switch on the PSU and let the power drain.

[Wolf Frost]

Yes that is similar to what I am experiencing. So long as it is shut down normally I can do the "quick tap" method to reboot it. However if I shut it down during post it is dead as dead can be until I turn off the rocker switch on the PSU and let the power drain.

 

 

Increasing my 5v knob also caused this problem. Decreasing it solved it.

[dfi_user]

Increasing my 5v knob also caused this problem. Decreasing it solved it.

 

i tried both increase and decrease the 5v rail, problem still same.

[red930]

Please get and use a quality multi-meter before adjusting the voltages on your PSU. While the included indicators are nice, they aren't accurate enough for you to trust them.

 

Keep your voltages as close to 12V, 3.3V and 5V as possible unless you have a specific reason to increase them.

 

Overvolts can cause stabilty problems as much as undervolts.