sharing a power supply

Alan Ward award at
Wed Jul 2 13:41:02 EDT 2003

Dear listpeople,

I am building a small beowulf with the following configuration:

- 4 motherboards w/ onboard Ethernet
- 1 hard disk
- 1 (small) switch
- 1 ATX power supply shared by all boards

The intended boot sequence is the classical (1) master boots off
hard disk; (2) after a suitable delay, slaves boot off master
with dhcp and root nfs.

I would appreciate comments on the following:

a) A 450 W power supply should have ample power for all -
but can it deliver on the crucial +5V and +3.3V lines? Has anybody
got real-world intensity measurements on these lines for Athlons
I can compare to the supply's specs?

b) I hung two motherboards off a single ATX supply. When I hit
the switch on either board, the supply goes on and both motherboards
come to life. Does anybody know a way of keeping the slaves still
until the master has gone through boot? e.g. Use the reset switch?
Can one of the power lines control the PLL on the motherboard?

Best regards,
Alan Ward

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