Here are some basic power consumption measurements for various old computers. This is not very scientific and more a matter of historical record. All measurements were taken with a P3 Kill-a-Watt P4400.

Model
Processor(s)
CPU Clock Memory Storage Peripherals Idle Power
Sun Blade 150
UltraSPARC IIi
1×550MHz
 
2×256 MB PC133 Unbuf ECC Seagate ST340014A
Samsung DVD/CD-RW ATA
  33 W
Power Mac G4
PowerPC 7450
1×933MHz 1×512 MB PC133
2×512 MB PC100
60GB IBM IC35L060AVVA07-0 ATA/66
2 × ST336754LW Ultra320/15k
Pioneer DVR-104 ATA 6X DVD-RW
ATI Radeon 9000
Adaptec ASC-29160N
69 W
Power Mac G4
PowerPC 7450
1×933MHz 1×512 MB PC133
2×512 MB PC100
60GB IBM IC35L060AVVA07-0 ATA/66
2 × ST373307LW Ultra320/10k
Pioneer DVR-104 ATA 6X DVD-RW
ATI Radeon 9000
Adaptec ASC-29160N
73 W
Sun Ultra 10
UltraSPARC IIi
1×360MHz 4×128 MB EDO ECC Seagate ST336754LW Ultra320/15k
LG CRD-8322B ATA 32X CDROM
Symbios SYM22801 75 W
Sun Ultra 10
UltraSPARC IIi
1×360MHz 4×128 MB EDO ECC Seagate ST336754LW Ultra320/15k
LG CRD-8322B ATA 32X CDROM
Symbios SYM22801
SunPCi I / 300MHz / 256MB
83 W
SGI O2
MIPS R5000
 
1×180MHz 6×32 MB PC133 ECC 9.1 GB SCSI
36.7 GB SCSI
  85 W
Sun Blade 1500 Red
UltraSPARC IIIi
1×1062MHz 4×512 MB DDR-266 ECC 1 × Seagate ST38011A ATA100/7.2K
Lite-On XJ-HD166S ATA 16X DVD
Sun XVR-600
Sun USB2.0/Firewire Combo
111 W
Sun Blade 1500 Red
UltraSPARC IIIi
1×1062MHz 4×512 MB DDR-266 ECC 2 × Seagate ST38011A ATA100/7.2K
Lite-On XJ-HD166S ATA 16X DVD
Sun Expert3D Lite
Sun USB2.0/Firewire Combo
122 W
Sun Blade 1500 Silver
UltraSPARC IIIi
1×1502MHz 4×512 MB DDR-266 ECC Seagate ST380011A ATA100/7.2K
Toshiba SD-R1512 ATA 16X DVD
Sun XVR-600
Sun USB2.0/Firewire Combo
138 W
Sun Ultra 60
UltraSPARC II
2×360MHz 8×64+4×128 MB EDO ECC Seagate ST1181677LCV Ultra160/7.2k
Toshiba XM-6201TA 32X CDROM
Sun Creator3D FFB3+ 153 W
Sun Ultra 60
UltraSPARC II
2×360MHz 8×64+4×128 MB EDO ECC 2×Seagate ST1181677LCV Ultra160/7.2k
Toshiba XM-6201TA 32X CDROM
Sun Creator3D FFB3+ 158 W
Sun Blade 1000
UltraSPARC III
1×750MHz 4×256 MB
4×512 MB PC100 ECC
36GB FC-AL 15K
Toshiba SD-M1401 SCSI 16X DVD
Sun PGX64 210 W
Sun Blade 2000
UltraSPARC III Cu
1×900MHz 4×256 MB
4×512 MB PC100 ECC
2 × ST373307FC FC/10k
Toshiba SD-M1401 SCSI 16X DVD
Sun PGX64
Sun Gigabit Ethernet
215 W
SGI Fuel
MIPS R14000
 
1×500MHz 2×1024 MB DDR-400 ECC Seagate ST373 series Ultra160/10k SGI VPro V12 223 W
Sun Blade 2500
UltraSPARC IIIi
2×1600MHz 4×1024 MB
4×2048 MB DDR-333 ECC
2 × Maxtor Atlas 15K II Ultra320/15k
DVD ATA
Sun XVR-100
Sun USB2.0/Firewire Combo
283 W
Sun Blade 1000
UltraSPARC III
2×750MHz 4×256 MB
4×512 MB PC100 ECC
36GB FC-AL 15K
Toshiba SD-M1401 SCSI 16X DVD
Sun PGX64 288 W
HP rx2600
Intel Itanium 2
2×900MHz 12×512 MB DDR-266 ECC 3× Seagate ST373 series Ultra160/10k   373 W