dell da-1 + 120w picopsu not posting

lesticx · Post by **lesticx** » Wed Apr 14, 2010 4:00 am

Hi,

this is a really weird problem. The system is:
intel dg45id microatx board
c2d e8400
500gb 2,5" disk
and i'm also powering a 17" lcd screen from a molex out (it takes 5 and 12v in)
Everything works fine with a standard 200w atx psu that has an old 20-pin connector, and power draw is around 90w idle with the screen.

And picopsu won't post. If I use a wire to start the picopsu separately, all the voltages are good and all the pins give what they're supposed to give. But it won't start my mobo. It does give power to the molex connectors though.

Ideas?

ryboto · Post by **ryboto** » Wed Apr 14, 2010 9:56 am

I had similar issues with the DA/2 and a PW-200M, the larger version of the Pico. Wouldn't post, just tripped the brick into "off" mode, and the light on the brick would go from green to orange. It might be an issue with the brick/Pico compatibility. Something to do with voltage/current ramp up time.

lesticx · Post by **lesticx** » Wed Apr 14, 2010 11:10 am

Well, this is different: only the mobo doesn't start up. Brick stays on, and all the peripherals keep running (hdd, the display etc).
I'll need to test if it passes both 12v and 5v to the molex connectors, but it seems to do so.

I'll test the picopsu with 12v input from that atx psu, when I have the time to wire it..

ryboto · Post by **ryboto** » Wed Apr 14, 2010 11:27 am

lesticx wrote:Well, this is different: only the mobo doesn't start up. Brick stays on, and all the peripherals keep running (hdd, the display etc).
I'll need to test if it passes both 12v and 5v to the molex connectors, but it seems to do so.

I'll test the picopsu with 12v input from that atx psu, when I have the time to wire it..

There is the possibility the pico and the board aren't compatible. I'd contact minibox about it. They were nice enough to talk to me over the phone when i had issues with the PW-200M.

lesticx · Post by **lesticx** » Thu Apr 15, 2010 12:22 am

ryboto wrote:There is the possibility the pico and the board aren't compatible. I'd contact minibox about it. They were nice enough to talk to me over the phone when i had issues with the PW-200M.

Thanks, I'll do that. So did you ever manage to resolve these issues you had, or did you end up changing to another power supply?

ryboto · Post by **ryboto** » Thu Apr 15, 2010 4:19 am

lesticx wrote:
ryboto wrote:There is the possibility the pico and the board aren't compatible. I'd contact minibox about it. They were nice enough to talk to me over the phone when i had issues with the PW-200M.
Thanks, I'll do that. So did you ever manage to resolve these issues you had, or did you end up changing to another power supply?

I ended up going from the PW-200M+DA-2 to the PicoPSU+DA-2. The guys at minibox couldn't explain it, since they said the designs are exactly the same, it's just that the Pico is a more compact version.

lesticx · Post by **lesticx** » Sat Apr 17, 2010 2:34 am

Right, after some testing this is getting even stranger..

Test 1: I used an old 200w atx psu to power the system as follows:
- connect 12v + ground from a molex to picopsu input wires (12v + ground)
- connect P4 from atx psu to motherboard P4

Great, works, no problems here.

Test 2: I wired the P4 connector so that it's coming from the same point, where that molex is wired into picopsu. Basically the 12v wire goes psu -> molex -> P4 & Picopsu
Now the system doesn't boot, fans just turn a little bit, mobo doesn't start. If I attach disks etc they work fine.

Test 3: use the same wiring as in test 2, but use Dell da-1 for power. Same results.

Unfortunately I only have one power cable

so I can't test so that I'd power the picopsu from da-1 and P4 from atx psu. I feels this might work.

There's two 12v lines coming from the da-1, which at the moment I've soldered together and into a barrel connector to connect the picopsu. I'm thinking it might work if I separated these lines again, and used one line for picopsu, and another one for P4.. ideas? This should be the next test, when I have time..

lesticx · Post by **lesticx** » Sat Apr 17, 2010 6:13 am

Still not working.. I measured the voltages off the pico, especially the pwr_ok pin. This doesn't seem to be ok.

The pico gives about 2.2v on pwr_ok, but my atx psu has it at around 5v. Is this picopsu simply faulty?

electrodacus · Post by **electrodacus** » Sat Apr 17, 2010 10:42 pm

lesticx wrote:Still not working.. I measured the voltages off the pico, especially the pwr_ok pin. This doesn't seem to be ok.

The pico gives about 2.2v on pwr_ok, but my atx psu has it at around 5v. Is this picopsu simply faulty?

I guess that the 5V on your PcoPSU is less than needed probably the monitor is to much.... try to start the computer without the monitor (not with the monitor in standby but without the 5V and 12V connected to monitor form PicoPSU )

lesticx · Post by **lesticx** » Sun Apr 18, 2010 9:53 am

electrodacus wrote:
lesticx wrote:Still not working.. I measured the voltages off the pico, especially the pwr_ok pin. This doesn't seem to be ok.

The pico gives about 2.2v on pwr_ok, but my atx psu has it at around 5v. Is this picopsu simply faulty?
I guess that the 5V on your PcoPSU is less than needed probably the monitor is to much.... try to start the computer without the monitor (not with the monitor in standby but without the 5V and 12V connected to monitor form PicoPSU )

I did, actually all those test were done without the monitor. Doesn't budge. But after some more careful measuring, it seems to pico gives 3.3v (not 2.3) on the pwr_ok pin after startup. It seems to me that the motherboard expects 5v.

Electrodacus, how is this signal with the winmate?

Also, I measured the current draw of the monitor: it only draws as follows:
- 5v: 0.5A
- 3.3v: 0.3A
- 12v: 2-3A

electrodacus · Post by **electrodacus** » Sun Apr 18, 2010 7:48 pm

lesticx wrote: I did, actually all those test were done without the monitor. Doesn't budge. But after some more careful measuring, it seems to pico gives 3.3v (not 2.3) on the pwr_ok pin after startup. It seems to me that the motherboard expects 5v.

Electrodacus, how is this signal with the winmate?

Also, I measured the current draw of the monitor: it only draws as follows:
- 5v: 0.5A
- 3.3v: 0.3A
- 12v: 2-3A

I just did a measurement and winmate outputs on pwr_ok pin is 5V so it may be that your motherboard expect the full 5V but is a digital signal so even 3.3V should register as OK.
You can try and connect the pwr_ok pin to 5V using a 10k resistor to see if this is the problem.
And if that is the current draw of your monitor then is no problem.

lesticx · Post by **lesticx** » Mon Apr 19, 2010 3:38 am

electrodacus wrote:
lesticx wrote: I did, actually all those test were done without the monitor. Doesn't budge. But after some more careful measuring, it seems to pico gives 3.3v (not 2.3) on the pwr_ok pin after startup. It seems to me that the motherboard expects 5v.

Electrodacus, how is this signal with the winmate?

Also, I measured the current draw of the monitor: it only draws as follows:
- 5v: 0.5A
- 3.3v: 0.3A
- 12v: 2-3A
I just did a measurement and winmate outputs on pwr_ok pin is 5V so it may be that your motherboard expect the full 5V but is a digital signal so even 3.3V should register as OK.
You can try and connect the pwr_ok pin to 5V using a 10k resistor to see if this is the problem.
And if that is the current draw of your monitor then is no problem.

Okay, i gotta ask b4 something blows.. would it be ok to just connect the pin to a 5V source? Is the resistor very necessary? I really am not an expert when it comes to elecricity, I'm pretty much way over my head in this project..

electrodacus · Post by **electrodacus** » Mon Apr 19, 2010 8:55 am

lesticx wrote: Okay, i gotta ask b4 something blows.. would it be ok to just connect the pin to a 5V source? Is the resistor very necessary? I really am not an expert when it comes to elecricity, I'm pretty much way over my head in this project..

You need a resistor to limit the current to max 20mA to be safe so any resistor from 470ohm up to 10kohm will work hope you have one.
But is just strange that you have 3.3V on pwr_ok pin and also strange that 3.3V is not enough to be considered "OK" by the motherboard.

lesticx · Post by **lesticx** » Mon Apr 19, 2010 10:41 am

electrodacus wrote:
lesticx wrote: Okay, i gotta ask b4 something blows.. would it be ok to just connect the pin to a 5V source? Is the resistor very necessary? I really am not an expert when it comes to elecricity, I'm pretty much way over my head in this project..
You need a resistor to limit the current to max 20mA to be safe so any resistor from 470ohm up to 10kohm will work hope you have one.
But is just strange that you have 3.3V on pwr_ok pin and also strange that 3.3V is not enough to be considered "OK" by the motherboard.

Ok, so I took my chances without any resistor, and hooked a 5v directly to pwr_ok.. didn't budge. I measured the voltage on PS_ON when pressing power switch, and it doesn't go low.. seems this picopsu is faulty, I'll return it.