Power requirements
Component Requirement Line(s) Used
High-wattage AGP card 20-50W +3.3V
Average PCI card 5W +5V
Cached SCSI controller PCI card 20-25W +3.3V and +5V
Floppy drive 5W +5V
10/100 NIC 4W +3.3V
50x Atapi CD-ROM 10 - 25W +5V and +12V
12x Atapi DVD-ROM 10 - 25W +5V and +12V
12x / 10x / 40x SCSI CD-R/RW 20W +5V and +12V
SCSI CD-ROM 12W +5V and +12V
RAM 8W per 128MB +3.3V
Ultra2 SCSI PCI card 5W +3.3V and +5V
7200rpm IDE hard drive 5 - 15W +5V and +12V
7200rpm Ultra2 SCSI hard drive 24W +5V and +12V
10,000rpm SCSI drive 10 - 40W +5V and +12V
Motherboard (without CPU or RAM) 20 - 30W +3.3V and +5V
Typical Pentium II 30W +5V
1GHz Pentium III 34W +5V
1.7GHz Pentium 4 65W +12V
1.4GHz AMD Athlon 70W +12V
hope this helps you to add up your requirements
peter