Asestar said:
Dear Ben.
I guess you're lucky to have stable system so far. But let me in you a
secret, 12.5V on a 12V rail is NOT safe. It has btw nothing to do with how
many watts it have.
Q-Tec's 550W = 365-400W of good make.
I totally understand that Q-Tec supplies are overrated - they're probably
rated for operation at around 20-25°C, which is clearly not the normal
operating temperature. The current available on each rail drops
significantly with increasing temperature.
12.5V is within spec and, is not "NOT safe" by any means. If I was using
the power supply beyond it's rated current output, I would expect the rail
to sag - the Voltage would drop, or at least vary under differing current
drain situations.
Q-TEC have a long history of lying about wattage of their psu's.
When others like Enermax, antec etc say 365W, they mean 365 watt of
continous power output.
Thats a strong assertion. I would say it's misleading, but outright lying?
A quick sum of the peak voltages and currents:
30*3.3+40*5+18*12+5+12+5*3 = 547W
Thats the peak. So you are probably right about how they justify their
ratings.
Same sum for continuous rating:
18*3.3+30*5+16*12+.5*5+.5*12+5*2.5 = 422W
So it's a ~420W PSU. It's labelled quite adequately on the side.
When Q-Tec label their psu 550W, it means 550 watt is the peak voltage
that psu *might* deliever for *unspecified* amount of time (could be an
hour, a second, who knows). Remember you get what you pay for.
I know.
You can't equate voltage with wattage. We should be talking about current
draw on each particular rail.
However, considering your hardware, power requirement is about 300-350W,
which your Q-TEC 550W might handel well. But never ever make mistake of
using this psu where acutally 400-450Watt of power is needed, it SHALL
fail there.
Maybe. I'm just saying that it does work fine on mine, and Voltages have
remained within spec (the other rails are much closer) throughout all kinds
of operating conditions.
Besides, they make a hell of noise, and there is no switch on psu. You
have to pull the plug to turn it off in emergency.
The switch is not really a concern of mine, if I can find the switch, I can
pull the lead out the back.
I have replaced both fans, knowing full well that they are noisy, as I had
the 450W before, on my old system.
Incidentally, this is one of the newer ones that is PFC approved, this also
helps a little with current drain as a PFC of .99 or better (I think thats
what the spec says, from memory) is going to give you the maximum current
for a given wattage.
Ben
