I'm upgrading my PC to an Athlon 64 3200+, 1GB RAM (2 x 512 DDR),
a single 200GB HD (not SATA), with a Radeon X800 XL PCIe graphics
card. I only have one DVD/CD RW combo drive, and one PCI expansion
card (a cheap 5.1 sound card).
I used a website to calculate the minimum PSU I should be using
and it said 260W. Since this is the peak power draw from all the
components combined, would my current 300W power supply be
sufficient?
We don't know the amperage ratings per rail on your 300W PSU
but the typical 300W model would not be sufficient. This
modern combination of parts puts a higher load on the 12V
rail and thus, what you're really looking for it's total #
of watts but # of amps on 12V rail (from a brand you trust
to give accurate labeled ratings, or that you have enough
experience with to de-rate appropriately. For example, many
generic so-called 500W PSU might be viable for use if
considered a "300W" PSU, not using in a system that needs a
real 500W PSU).
PSU generally make leaps in amperage too, it's not as though
it's common to see one with 13A, and knowing you want at
least 14A, to then keep looking till you find one with only
another amp instead of the next larger size which might be
16A or 18A, etc, etc. Your parts aren't as power hungry as
some, you can probably get by fine with any decent name
brand rated for 18A of 12V current, but even more is better
if you had plans to upgrade the system some or a total
upgrade by replacing the board/CPU/etc again as you're
doing this time. So you don't really need a good 500W PSU
but 300W in most PSU would be borderline, unless it's one of
the very latest 300W models that may be biased towards
providing most of those watts on the 12V rail. Anything
more than 2 years old certainly wouldn't be.
