I have Dell XPS400 desktop pc . the problem it has only USB Ports and requires USB Keyboards and mouse now all the ports are not functioning and the system prompt to press F1 or F2 key to go ahead but keyboard not detected so nothing is working.
If you have difficulty with the steps in "Hardware Reset" you can refer to the Service Manual by clicking here. Refer "Clearing CMOS Settings" section of the manual on page number 30. If these steps do not fix the issue try using a different keyboard and check (the problem could be with the keyboard and mouse also).
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