"Lars-Erik Østerud" .@. wrote in message


[...]

3A will be 36 watts, right. But I haven't the faitest idea how much
power a P4 2.54GHz draws. The DVD-writer don't pull any power for
writing during 3D gamplay anyway. What about my S-ATA 250GB HDD?

The CPU isn't the only factor, as it runs at about 1.5v anyway, but you also
have to factor in its cooler, not to mention the motherboard itself.
Regarding the HD, to pick an example, the Seagate Barracuda 7200.9 250GB
draws up to 2.8amps at spinup, around 1amp during ordinary use.

That's about it. What will happend if the PSU is to small anyway?
Can anything get damaged if the PSU can deliver (or breaks down)?

What I've seen happen is people getting an error message about the 7600GS
AGP being underpowered and running at a reduced rate. Usually that's
because they forget to plug in the Molex connector but in one case recently
I got the chap in question to shuffle his power connectors around to
distribute the load across different rails as he had both the card and his
hard disks all hanging off one rail (I couldn't tell you what its nominal
capacity was though). You obviously couldn't do that though, with only one
12v rail.

I'd rather buy a new PSU, but all the good ones lack the -5V line, and
even if I have no ISA devices I'm afraid to damage my motherboard if I
plug in a PSU without the -5V (I have an Asus P4PE motherboard)

Google this group or alt.comp.periphs.mainboard.asus on the -5v issue. I
remember reading recently it's an artifact from seriously old systems and
the lack of -5v on newer PSUs shouldn't be a problem.