Assistance in resurrecting my Unitech K959

[Aruberon]

Hi DT, long time lurker, recent ish registrator, first time poster.

Im a bit at a loss with one of my boys, and before tossing it out for spring cleaning perhaps DT could shed some light on why my Unitech K959 is dead.

It was a recent-ish purchase, been dead for as long as I've had it.
Overall looks to be in good condition but im not the most technical when it comes to electrical knowhow, so at best I have some wild suggestions, but I have access/the ability to do some light soldering.

The boy without his case (highscreen edition as per wiki/Unitech_K959#Parex_MODERN-I_REV.1_ ... 22_branded, but not with any of the listed switches)

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The XT/AT switch appears to be working(?), when plugging it in while in XT mode the locklights briefly flicker, im not expecting it to work in XT mode on a regular machine but its the only sign of life its given me, swapping it to AT mode however, there is no life.

The traces and solder look relatively ok, except for the top left, which happens to be the XT AT switch, possible issue?

Furthermore, there is the "quality" ground cable, which I have to assume is factory, another cause for concern maybe? I've had boards with grounding issues before, but they tend to have a seizure rather than be perma dead.


I thank you all in advance for any suggestion which may help resolve this issue, or atleast we might learn something
-Dan

[Muirium]

but not with any of the listed switches

Well what switches, then? I doubt they're all dead, just curious.

[Aruberon]

but not with any of the listed switches

Well what switches, then? I doubt they're all dead, just curious.

The switches themselves are probably fine, cant verify but considering locklights dont react at all in AT mode, probably something else.
Anyhow, I didnt dig any deeper but they look like this:

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Linear, fairly light, not scratchy.
They look fairly generic so I have no idea if its an authentic switch or a clone.

[Muirium]

Those are different. Dunno what they are, but I'm no switch ID specialist. Thanks for the pics.

The keyboard sounds like it's got a faulty controller, as everything's down at once. Usually electrolytic (big tube shaped) capacitors leaking, losing their capacitance and stopping the whole show. There's two I can see in your pics, including the black and white thing marked 50v next to the Intel controller chip. Look for residue.

[Aruberon]

I suspected the caps, but they look clean and arent swollen, no residue on either board or the caps themselves

If it comes to desoldering either the AT/XT switch or anything else, I suppose I can undo one of the switches as well just to open it up to see what it is, the inside is probably fairly ordinary however