All-In-One 24-df1000 not powering up after adding memory

[pb02476]

Owned All-In-One 24-df1000 for one year, installed Ubuntu 24.04, and used on vacattion last summer, put it back in the box last fall to bring it home to add memory.

Opened it up without testing it first, put in a used 8GB Kingston SODIMM, tried powering it on before closing it up.

Power light on back is on.

When pushing power on button, front power light lights, goes out, and gives a tiny blip.

No fan, beeping, or anything on display

Things I've tried:

1. different power outlets
2. different power supply brick (higher wattage from an HP Pavilion 27")
3. disconnected from power, plugged back in, held power on button for 60 seconds
4. removed motherboard battery for over an hour
5. no memory installed
6. just old memory installed
7. tested keyboard on another computer
8. with and without mouse/keyboard
9. replaced the button/reader card

Any thoughts on connectors to look at?  Secret handshakes??

Anything else to try before getting another motherboard??

Thanks!!!

[BeemerBiker]

Put the original memory back in.  If there is a slot named "slot 0" for "Dimm-1" then use that slot and only one stick of memory.  Use air duster first.

do a hard reset

• Turn on the computer by holding the power button down for 20 full seconds then release.
• Press the Power button one more time (if necessary) to start the computer.

Follow the steps below to reset computer CMOS data.

1. Turn off the computer.
2. Press and hold the Windows and the V keys.
3. While still pressing those keys, press and hold down the Power button on the computer for 2-3 seconds.
4. Release all the keys.
5. At the completion of a successful CMOS reset, a message showing CMOS Reset (502) will be displayed.
6. Restart the computer.
7. Press F10 to get in to bios. Check Date and time.
8. Press F9 to set bios defaults. Ensure secure boot is enabled.
9. save setting when you exit