Measuring the power supply

200-300 watts is enough.

How can I be more specific if you don't provide info about the CPU, motherboard and memory? If you need very precise power requirements, then you'll have to use sophisticated measuring equipment. What's your goal?

Be more specific.

A 4.1 GHz Pentium D 805 would consume 474 Watts at load.
An E7200 at stock and loaded could survive with a 250W psu.

thelivingflesh is right with the HX1000, until you provide more info.

What i mean is: in the avarage case, and in avarage load, how much WATT do you think the PC consume?

How much of it does the CPU+mobo+memory consume, taking out all the remaining components (graphic card, HD, CDs etc..)

If you think that some other forum here in this site might help me, please let me know.

"What i mean is: in the avarage case, and in avarage load, how much WATT do you think the PC consume?"

Define the average PC. Do you mean the average PC based on the world population, the U.S. population, or the extremely unusual average of the regulars here - keeping in mind that we are enthusiasts.

Example from about 3 years ago (I was curious ...):
eVGA 680i motherboard, Q6600 OC'd to 3.6 GHz., 2 GB RAM, G80 core 640 MB 8800GTS, 2 HD, 1 optical, Audigy sound card, Antec 650 watt TP3 PSU

I borrowed a lab calibrated clamp-on ammeter probe from work to measure actual power consumption at the motherboard.

(As I check my notes)
I measured by separating wires and clamping the probe around all the same color wires in the bundle.

CPU (8 pin EPS cable) : 9.5 amps @ 12 volts. = 114 watts (while running Prime95)
GPU (6pin PCI-e cable): 7 amps @ 12 volts = 84 watts (while running 3DMark05)
2 GB RAM (orange wires) : 3 amps @ 3.3 volts = 10 watts
Motherboard : 5 amps @ 5 volts, 3 amps @ 12 volts = 61 watts
Drives - total (peak) : 3 amps @ 5 volts, 3 amps @ 12 volts = 51 watts from dataplates

There's a lot more electronics on the eVGA motherboard than there are on my Gigabyte motherboards.