Yeap, it's dead!
Caps Lock blocked, no error-codes on boot (even the rom won't check itself), no "early startup menu".
Sorry I don't have a Warp-card (I had a standard A3640). Might be the RAM modules on the card?!. Check some info on this (if it can be started without ram: es. the CSPPC won't boot without 1 pair of simm at least!).
Suspects: (from the least serious damage)
-RAM
-ROM
-CPU card
(from the most highly probable order)
-CPU card (when not fitted well always gives a black non-responsive screen when you turn on the AMiGA).
-ROM (won't do the self-check procedure on boot)
-RAM (see the CSPPC example, I don't know for the Warp card)
The PSU might be also, but in low voltage you wouldn't have the caps lock ligth blink even for once.
I think it's the 5V for the mobo power, the 12V for the HDs etc. You have nothing to lose if you check the power output with a tester (you said that it's not the original PSU...)
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MERCEDES-BENZ 280