A power supply will deliver what ever current is demanded by
the load on the system. A poor PSU will over-heat and
burn-out while a good PSU will shut-down before it gets that
hot.
Further, the amperage will go up and the voltage will drop
when the unit is over-taxed, a 400 Watt PSU will live
happily giving 250 W 24/7/365 while a 250 W PSU (a cheap
one) will run hotter delivering the same 250 Watts and may
not perform as well under surge loads, such as starting all
the drives during the boot process.
Add the total loads expected, allow for growth, and then buy
a PSU that is at least 125% of that total.
--
The people think the Constitution protects their rights;
But government sees it as an obstacle to be overcome.
| ~ßïtzChiçk~ wrote:
| > Please could you advise on what determines whether you
go for 300W or
| > 400+W psu when building a new computer
|
|
| The answer isn't quite as simple as a 300W unit or a 400W
unit. Many many
| manufacturers rate their power supplys in a non-standard
manner. On the
| bench as well as in practice, a quality 300W unit may
supply more current
| than a shoddily made 420W unit.
|
| Choose from an Antec, Enermax, Sparkle/Fortron Source or
Enlight. Expect to
| pay £55-60, for a good 400W unit.
|
|