"The maximum +12V current is 500mA.
The maximum current that you could draw from +3.3V is 7.6A, because that
works out to 25W, assuming zero current on all the other supply
voltages. But this limit is "system dependent," so a given system might
not have the full 7.6A available for a slot even if it is the only PCI
card in the system. A system might balance the power capabilities
differently between the +5V and +3.3V (and +/-12V) supplies, rather than
making 25W available from +5V and 25W available from +3.3V.
The maximum current from +5V is 5A, with the same conditions as above
for the +3.3V supply."
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