The Hard Drive current draw restrictions:
On the K2000 Keyboard:
0.6 Amps on +5 volts 0.75 Amps on +12 volts
(possibly up to 10% more)

On the K2000R and K2500R Racks:
1.0 Amps on +5 volts 1.0 Amps on +12 volts
(possibly up to 10% more)

As far as memory size, many 1 Gig sizes who meet the current draw requirements seem to work.

If you have a K2000 or K2000R without P-RAM, you can not Backup between two drives if the total is greater than 1 Gig. If you have P-RAM or a K2500R, you can back up between two large drives with no problem.
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