I'm planning a new system, it'll be my first Pentium 4. How many watts do I
need for a P4P800, a P4c 2.6 or 2.8 GHz, 1GB of RAM, 4 hard drives, a CD burner,
and an ATI Radeon 7500?
A quality 300W PSU will probably be enough. A poor quality 400W PSU
will not be. Look for a healthy +12V line, with 15A or more. The total
wattage rating of a PSU is misleading, and in some cases, a total lie.
You need to look at the individual output of the PSU on its 3V, 5V and
12V lines and use your own judgement.
For example, this PSU is rated at 300W:
http://www.newegg.com/app/viewproduct.asp?DEPA=1&submit=Go&description=P300XFPN
This one is rated at 400W:
http://www.newegg.com/app/viewproduct.asp?DEPA=1&submit=Go&description=Allied,400W
Yet both have exactly the same output limits (28A, 30A, 15A
respectively). The Fortron is also the better PSU: quieter and better
built. Many branded PSUs, such as Nexus, Zalman or SilenX, are built
using Fortron PSUs with some minor modifications.
Depending on what you're looking for (quietness, overall power, etc.),
look into getting something with a brand name. Seasonic or
Fortron-based for quality and quietness, Antec for quality and power
output.
SPCR has a good thread about this topic:
http://forums.silentpcreview.com/viewtopic.php?t=3075
Max Attar Feingold
maf6 at cornell dot edu
http://almonaster.sourceforge.net/mfeingol/
Not speaking for my employer
