Power Supply Calculator,http://extreme.outervision.com/psucalculatorlite.jsp
A) System Type: 1 physical CPU (Processor)
B) Motherboard: High-end desktop (KN1 Extreme)
C) CPU Brand: AMD
4) CPU Socket: Socket 939
5) CPU: Lord only knows. I chose a Processor that uses Up To 89 Watts. AMD Athlon 64 4000+ 2400MHz San Diego 1.35v
6) CPU Utilization TDP: 90% TDP (recommended)
(In otherwords leave alone)
7) Overclock my CPU!: Leave alone
8) RAM: 2 sticks of DDR SDRAM
9) Video Cards;
A) Video Brand: AMD (AMD owns ATI now)
B) Video Card 1: AMD Radeon HD5450
C) Video Card 2, 3, and 4: Leave alone
D) Video Type: Leave alone
E) Physics Processing Units: Leave alone
10) Hard Drives:
A) Regular SATA: 1 HDD
11) Go to Drives;
DVD-RW/DVD+RW Drive: 2 Drives
12) Go back up to the right; PCI Cards:
I left alone. Only you know at present, if you are using one, or more of these types of PCI cards.
13) Go to Fans;
80mm / Regular / 2 Fans. (Just guess-timating)
All fields should be entered now. If not make adjustments to what I didn't know. Include in the proper field.
Now go to the bottom right, and click on - Calculate
(Calculate / Reset / Print )
I come up with 265 Watts.
Want to know EXACTLY what hardware is used inside; without opening the computer case?
Use the tiny free program, CPU-Z from CPUID.com
(Can help you download, install, and use, CPU-Z if you need.
I have used CPU-Z for years)http://www.cpuid.com/softwares/cpu-z.html
For additional questions please post in a Comment.