cyrnel

The startup mode issue sounds like legacy USB support is disabled in your BIOS.

If it's cutting out randomly while windows is booted then I'd suspect a cable, controller, or excess power draw. How many and what things are plugged in to the computer USB ports? (not counting powered hubs) Have you ever seen an alert to that effect?

Do you have one of the little USB/PS2 adapters that usually ship with keyboards? Try the same keyboard plugged into the PS2 port and see if the problems change.
Try another USB port. Best would be a separate USB card, if your system has one.
Try another keyboard, at least temporarily.

The startup mode issue sounds like legacy USB support is disabled in your BIOS.

If it's cutting out randomly while windows is booted then I'd suspect a cable, controller, or excess power draw. How many and what things are plugged in to the computer USB ports? (not counting powered hubs) Have you ever seen an alert to that effect?

Do you have one of the little USB/PS2 adapters that usually ship with keyboards? Try the same keyboard plugged into the PS2 port and see if the problems change.
Try another USB port. Best would be a separate USB card, if your system has one.
Try another keyboard, at least temporarily.

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There are a vast number of people who are uninformed and heavily propagandized, but fundamentally decent. The propaganda that inundates them is effective when unchallenged, but much of it goes only skin deep. If they can be brought to raise questions and apply their decent instincts and basic intelligence, many people quickly escape the confines of the doctrinal system and are willing to do something to help others who are really suffering and oppressed." -Manufacturing Consent: Noam Chomsky and the Media, p. 195