Thread: Looking for a creative solution: USB bus still powered after CPU is off

Originally Posted by rando

Update .... this did eventually cause some problems. On occassion, the Opus failed to turn on. I assume this means Ricky was right. The Opus probably does need to see the +12V line go high (at least) a bit before ACC.

Yes I did this. Without the +5V standby power, the M10k will pull the PSON signal low. This will cause the Opus to turn on. The Opus will then notice that ACC is low and turn back off. The pattern will continue (on, off, on, off, ...). To avoid this, you need to interrupt the PSON signal. What I did was put a DP relay on +5 standby and PSON. The relay is triggered as in ScouseMonkey's diagram. So far, this seems to work. I don't think this solution will support standby/resume mode.

So am I correct in saying that the only modification you did was:

Put a DPST relay on PSON and PSBY so that they were only connected when the ACC line was high or the computer was on(HDD power)?

why mod your 200$ psu, and invalidate the warranty, when you could simply get a molex, run a switch, and bypass all of these problems ? Am i missing something, you can also buy extra cigar lighters, and run them descreatly (spelling) so they will be out of view. Sorry if im missing somethin.
Thanks!

Originally Posted by RogerWilco

why mod your 200$ psu, and invalidate the warranty, when you could simply get a molex, run a switch, and bypass all of these problems ? Am i missing something, you can also buy extra cigar lighters, and run them descreatly (spelling) so they will be out of view. Sorry if im missing somethin.
Thanks!

I'm not modding the PSU, I'm putting a relay inline with the ATX power cable.

Molex cables don't do power load balancing, handle startup spike, or prevent shorted usb devices from drawing too much power.

Not to mention this mod will allow the motherboard to run normally, as opposed to hacking in a seperate power supply for USB devices which doesn't provide all of the USB power protection.

Also the mod you are suggesting can only be done on USB ports that have a header on the motherboard. The EPIA M10000 has 6 ports, 4 with headers, and 2 on the back panel. Your mod would not allow you to shut down the 2 on the back panel, unless you want to disconnect and resolder the connectors on the back panel.

PS: Stop posting, let your computer rest....

haha lol its had plenty of rest! for the last 8 hours almost ! i went to a family reunion, about an hour from my house. Anyways, i was unaware (seeing as ive never used one) that the molex connector was unregulated, i was under the impression that it was. Alright looks like i'll stray from ever using one in the near future. My bad there i misunderstood how you had run the relay, did you use a ATX12v extenison cable, and not directly cut the one from the psu ?
Thanks!

Originally Posted by RogerWilco

haha lol its had plenty of rest! for the last 8 hours almost ! i went to a family reunion, about an hour from my house. Anyways, i was unaware (seeing as ive never used one) that the molex connector was unregulated, i was under the impression that it was. Alright looks like i'll stray from ever using one in the near future. My bad there i misunderstood how you had run the relay, did you use a ATX12v extenison cable, and not directly cut the one from the psu ?
Thanks!

The OPUS has an external ATX cable that you plug into it and the motherboard; I will be modding that one.

The molex power cable is regulated, but not as much as the USB power supply.

oooh i forgot about that! my bad i have'nt actualy seen an OPUS power supply before, mines due this wensday. Very cool so i guess that would still keep the warranty. I'll have to look into this if i decide to use my full size optical dvd reader. Oh just thought of this, does the Opus 150w psu come OEM? or does it include the atx12v cable, and the HD connectors? (i bought it from mp3car.com)

will have to save that schematic,
ps you should post this in the sticky'd schematics thread

Thanks for taking the time to post the schematic.