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"No POST", "system won't boot", and "no video output" troubleshooting checklist This checklist is a compilation of troubleshooting ideas from many forum members. It's very important to actually perform every step in the checklist if you want to effectively troubleshoot your problem. 1.Did you...
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see step 17 here, the diagnostic speaker needs to be connected to the motherboards front panel connector, the headphone or speaker jack on the soundcard will not work for BIOS beeps. connect the speaker boot the system and listen for beeps.
cases used to come with a speaker already connected and motherboards came with the buzzer in the package, to save a nickle they removed that feature and increased the price to boot. you need to supply your own speaker now.
example only, not a suggestion, not an endorsement
https://www.amazon.com/dp/B01MR1A4NV?tag=duckduckgo-ffab-20&linkCode=osi&th=1&psc=1
one of these used to come with each motherboard once upon a time.
canned diagnostic speaker rant: speaker making 101
The diagnostic speaker is the motherboards main diagnostic feedback device.
the motherboard may be telling you where the problem is.
my speakers have this plug
http://images.crutchfieldonline.com/graphics/infolib/homelib/hSpeakerSpringClip.jpg
I use lamp wire but any stranded wire will do. literally any stranded wires. strip one end like so
http://www.antiquelampco.com/Shades/CordColors.jpg
attach the stripped end into the speaker spring clips on the speaker.
the other end of the wire should be trimmed like so the semi strip
https://wesbellwireandcable.com/images/cutwire.png
by doing a semi strip the wire case is now the socket.
plug one wire to the first pin, and the second onto the fourth pin.
power on the system and listen for beeps
end canned rant