Remember I told you about the switch and LED pins? This is counterintuitive. Diagram I made illustrates this.

Cheers,

pentiumspeed wrote on 2023-02-12, 02:59:

Remember I told you about the switch and LED pins? This is counterintuitive. Diagram I made illustrates this.

Cheers,

I’m sorry to be frustrating you. I followed your diagram. I can no longer short the power pins to start the board when connected to ATX power. I could before, but it doesn’t work now for some reason. I must be missing something. If you have any ideas as to why I can no longer short those pins to get the board going, I’d be very appreciative of the advice.

What I need is find a graphical drawing program and draw one for this kind of board to show what jumper block markings are for.

Cheers,

pentiumspeed wrote on 2023-02-12, 22:42:

What I need is find a graphical drawing program and draw one for this kind of board to show what jumper block markings are for.

Cheers,

I know what jumper block markings are for. I am following your diagram. Here is a photo of what I have hooked up. I’m just trying to get power from a power button with ATX.

If you see what I’m doing wrong with this connection, let me know. If there is something else I need to hook up or short, please tell me, because as of now when I press the button nothing happens.

Hi,

Keylock in green, ignore this for now, this is combined power LED and keylock, that's standard pinout using 4 wires.
Speaker in Yellow. Ignore for now.
Hard drive LED in red, Ignore for now.
Power switch in purple is what you momentarily short for ATX PSU.
Reset Switch is also momentary closed to reset the powered motherboard in Orange.

SSW and SUSLED are for standby which are not used.

Cheers,

Make sure your black and white wires is actually momentary power button. Some have push on, push off, you can tell by sound of click and the button are in different positions.

Make sure the resistors next to the jumper block is not blown as I sometimes get sparks if I touch wrong pins to that power switch pins.

Cheers,

pentiumspeed wrote on 2023-02-13, 01:26:

Make sure your black and white wires is actually momentary power button. Some have push on, push off, you can tell by sound of click and the button are in different positions.

Make sure the resistors next to the jumper block is not blown as I sometimes get sparks if I touch wrong pins to that power switch pins.

Cheers,

I think the resistors may be blown. It is a plausible explanation for why I can’t power on the board with the screwdriver trick anymore. I have a multimeter but have little experience using it - if you don’t mind me asking, how do I check the resistors? And how do I replace them?

The motherboard still works great under the traditional AT power connector. Would it not work if the resistors were blown?

Thanks for the insight! I appreciate it!

pentiumspeed wrote on 2023-02-13, 01:26:

Make sure your black and white wires is actually momentary power button. Some have push on, push off, you can tell by sound of click and the button are in different positions.

Make sure the resistors next to the jumper block is not blown as I sometimes get sparks if I touch wrong pins to that power switch pins.

Cheers,

Looking over the board again, where exactly are the resistors next to the jumper block? Not sure what they look like/how to test them.

Let me know, thanks!

Look at the tracks connecting to resistors from the pin headers and check the resistors next to the jumper header.

Cheers,

From my old experience with VIA MVP3/ALI ALADDIN AT format boards with dual power connectors (AT/ATX) some had jumpers for selecting the power supply type. I remember this because at the beginning one got fried because i did't knew to change the jumper position and they were set by default for AT power supplies (and that's the type of cases we sold most of them). But this time the client wanted a AT board with a ATX case/power supply. After i connected the ATX power supply and tried to turn (didn't post) it on the board wouldn't post with a AT power supply also (the board tested ok because we would test them before mounting them in to the case).

pentiumspeed wrote on 2023-02-16, 17:59:

Look at the tracks connecting to resistors from the pin headers and check the resistors next to the jumper header.

Cheers,

Hi,

Sorry for the extremely late reply - I ended up taking this board to a local computer repair shop and it turns out I shorted that pin header connector. In the end I ended up abandoning this particular PC build. The motherboard still works great under AT power; I currently have no plans for it. However, I did want to thank you and everybody else who contributed to this thread for all the help and support I was given. VOGONS is a really great community! I hope to return the favor someday.

Thank you again.

bogdanpaulb wrote on 2023-02-16, 18:29:

From my old experience with VIA MVP3/ALI ALADDIN AT format boards with dual power connectors (AT/ATX) some had jumpers for selecting the power supply type. I remember this because at the beginning one got fried because i did't knew to change the jumper position and they were set by default for AT power supplies (and that's the type of cases we sold most of them). But this time the client wanted a AT board with a ATX case/power supply. After i connected the ATX power supply and tried to turn (didn't post) it on the board wouldn't post with a AT power supply also (the board tested ok because we would test them before mounting them in to the case).

Thanks for the reply! I'll be sure to keep that in mind if I ever come across another board with both AT and ATX power connectors.

Looking at the pic of your mobo in OP I see two transistors in the vicinity of the front panel header. I would check those. See if they are any good.

Also, kinda curious, it looks like your mobo has a header for a EISA slot. But it’s kinda a late mobo to be having that. Odd.

A round about way to regain soft off on your psu would be to adapt the AT power connector to atx. Check out the pico psu adapter project
ATX to AT pico Adapter! + Fan Headers Soft on/off, -5v, and 3.3v (Released)