PSU wattage

[slaves123]

I'm about to buy a:
A64 2800+
asus k8v-x
512mb ddr400 supertalent memory
dvd-r
ati radeon 9600xt
80gb seagate barracuda hd

do u think that the 420watt PSU that comes with the case will be enough? no OC is planned at this time, at least now

thank you very very much

-Mauro-

 

[o1die]

Yes. But stable voltages are just as important. Check the hardware monitor sometimes called "pc health" in the bios when you first post. For 12v, I wouldn't use anything less than 11.7.

 

[CheesePoofs]

Any 420w PS should be more than enough, if you want to be completely sure look on the power supply to make sure it has an amperage rating in the high teens or higher for the 12V rail.

However, i wouldn't trust the bios to correctly measure the voltages of your power supply, they rarely show the correct numbers. Instead, if you want to check the voltages, download MBM or a similar program and as you run a stressful program like prime 95, watch the voltages and see if they jump around a lot. If they don't, you're fine.

 

[Zebo]

Originally posted by: slaves123
I'm about to buy a:
A64 2800+
asus k8v-x
512mb ddr400 supertalent memory
dvd-r
ati radeon 9600xt
80gb seagate barracuda hd

do u think that the 420watt PSU that comes with the case will be enough? no OC is planned at this time, at least now

thank you very very much

-Mauro-

supertalent?? asus k8v-x??? I'm more worried about those.

Check out some crucial/mushkin/corsair value ram first and ASUS K8N same price and way better chipset.

 

[BonzaiDuck]

Somewhere back I posted a list of "outside" (maximum) wattages for each and every component. For instance, a rule of thumb might be 4 Watts from the 12V rail for each fan, but this depends on the fan's amperage draw, so it could be less, or even more -- up to the limit of 12 watts (Vantec Tornado). Add in something like 60-90 watts of 12V for the processor; 20 to 30 watts of combined 3.3, 5 and 12V for the mobo; 20 watts of 3.3V for each 256MB of RAM; 5 to 10 watts of 5V for each PCI card; 20 to 50 watts of combined 5V, 12V and 3.3V for the AGP; 5 to 15 watts of 5V and 12V for a 7200 rpm hard disk; 5 watts of 5 and 12V for a floppy and 20 watts of the same rails for a CD device. LEDs are hardly worth counting at less than a watt each, and cold cathodes are about 3 watts of 12V.

Cheesepoofs is correct about the importance of noting voltage changes under load, and given my "hard-way" experience of less-than-optimal choices, I'd say take a look at the reviews that demonstrate extensive lab-testing, and see if you can find the power supply (at any rated wattage -- your 420 for instance) which has the steadiest lines. Two reviews on the same make and model may tell you if that model is a tad anemic or deficient on some rails. It may be fine for a particular power supply to show a sampling of units chronically measuring between 11.8 and 11.9 on the 12V rail, but the proof of the pudding is a stress test, and whether the rail's voltage drops even a tenth of a volt under load. A drop from 11.8 to 11.6V is either reason not to buy that model or, if you intend to over-clock, serious reason to buy another make and manufacture.

As to "promised wattage." Sometimes a manufacturer's "500" model won't sustain 480 under certain common conditiions. Other times, the "500" model is conservatively labeled and might justifiably be called the "550" or the "600". And sometimes, digging through enough reviews will reveal which is the case.