Do you think my PSU is powerful enough?

[eric.jentile]

Hi,

I have a homebuilt PC whose specs are:

MB Asus P4G8X
Pentium IV 3.06 Ghz
2 x 512 Mb Ram (PC 2100)
ATI Radeon 9700 PRO card
120 Gb HDD
1 CDRW
Moreover I use the USB ports to powersupply these:
1 ADSL Modem
1 Scanner
1 Optical Mouse

My PSU is the original one found in my case, that is a 300W Enermax. Do you
think it's enough? Should I power up?

Thx in advance

Eric

 

[SteveH]

Hi,

I have a homebuilt PC whose specs are:

MB Asus P4G8X
Pentium IV 3.06 Ghz
2 x 512 Mb Ram (PC 2100)
ATI Radeon 9700 PRO card
120 Gb HDD
1 CDRW
Moreover I use the USB ports to powersupply these:
1 ADSL Modem
1 Scanner
1 Optical Mouse

My PSU is the original one found in my case, that is a 300W Enermax. Do you
think it's enough? Should I power up?

Thx in advance

Eric

As its an Enermax, and they are usually decent PSU's you may well be ok. If
all the devices power up and it's not crashing, there's your answer!!

SteveH

 

[jeffc]

Hi,

I have a homebuilt PC whose specs are:

MB Asus P4G8X
Pentium IV 3.06 Ghz
2 x 512 Mb Ram (PC 2100)
ATI Radeon 9700 PRO card
120 Gb HDD
1 CDRW
Moreover I use the USB ports to powersupply these:
1 ADSL Modem
1 Scanner
1 Optical Mouse

My PSU is the original one found in my case, that is a 300W Enermax. Do you
think it's enough? Should I power up?

Yes, you will have to power up your computer to see if it works Here is
some free advice
http://www.upgradesource.com/advice/advice061001.html

 

[MikeW]

It will work. However, I think I'd want a bit more of a margin. 350W
would be better.

 

[Guest]

MB Asus P4G8X
Pentium IV 3.06 Ghz
2 x 512 Mb Ram (PC 2100)
ATI Radeon 9700 PRO card
120 Gb HDD
1 CDRW

My PSU is the original one found in my case, that is a 300W
Enermax. Do you think it's enough? Should I power up?

Most 300W power supplies won't be adequate for that setup, despite the
fact that it probably consumes only 150-200W, because rating standards
are virtually nonexistent. But Enermax is a decent brand, and it may
work, especially since that motherboard uses the +12V line for the CPU
power, meaning the supply will run way below its maximum combined
power rating for the +3.3V and +5.0V, probably 160-220W. Still, I'd
take voltage measurements with a meter, both with everything removed
but the motherboard and with all the equipment installed, and if any
voltage differs by more than 3%, the supply may be overtaxed. If you
find this to be the case, get a top quality 350-400W supply, and
Fortrons (Sparkles) are very cheap from sources like Directron.com and
Newegg.com.

 

[w_tom]

300 watts is typically more than enough power. Even running
the machine to 'prove' supply is sufficient is not a reliable
test. Knowledgeable hardware people use a so inexpensive and
ubiquitous 3.5 digit multimeter. As power supply reaches
extremes (but computer does not crash), DC voltage dip would
indicate an impending problem. Where to make those
measurements is in chart at:
http://www.hardwaresite.net/faqpowersupply.html

Is it safe to power up? Any power supply that comes with a
long list of necessary specifications can even have all
outputs shorted together and still not be damaged. Short
circuit must never damage any acceptable supply. Same power
supply would contain other circuits so that supply cannot
damage computer components. Standard knowledge to those with
the most basic computer knowledge. Enermax traditionally is
one of those properly constructed supplies. Therefore damage
from powerup should not be a worry.

Just power it up and get most everything active, while
monitoring those DC voltages - especially 3.3, 5, and 12
volts. If voltages remain stable, the power supply is
sufficient.

 

[jeffc]

300 watts is typically more than enough power. Even running
the machine to 'prove' supply is sufficient is not a reliable
test. Knowledgeable hardware people use a so inexpensive and
ubiquitous 3.5 digit multimeter. As power supply reaches
extremes (but computer does not crash), DC voltage dip would
indicate an impending problem. Where to make those
measurements is in chart at:
http://www.hardwaresite.net/faqpowersupply.html

Tom, I don't understand that test. It seems to test to see merely if the
power supply is putting out the voltages specified for each lead. This
isn't the same thing as testing to see if the wattage output is correct
under full system load. Do I misunderstand something here?

 

[w_tom]

Test measures voltage. Correct. When power supply
approaches too much load, then voltage starts to drop off - as
seen by the meter. Voltage and power remain sufficient for
computer to keep running, but a dropping voltage with load
increase means the power supply is approaching upper limit.

Short of expensive test equipment, your most effective
solution is using that 3.5 digit multimeter. If data is not
understood, then post it. Without those numbers, then every
response will only be speculation. You want facts; not
speculation. Does power supply provide sufficient power?
Power up everything and measure voltage (ie. while drives are
being accessed, etc). Currently insufficient numbers are
available. That multimeter is so inexpensive and required for
future hardware work. Get the meter to make numbers
available.

 

[jeffc]

Test measures voltage. Correct. When power supply
approaches too much load, then voltage starts to drop off - as
seen by the meter. Voltage and power remain sufficient for
computer to keep running, but a dropping voltage with load
increase means the power supply is approaching upper limit.

Short of expensive test equipment, your most effective
solution is using that 3.5 digit multimeter. If data is not
understood, then post it. Without those numbers, then every
response will only be speculation. You want facts; not
speculation. Does power supply provide sufficient power?
Power up everything and measure voltage (ie. while drives are
being accessed, etc). Currently insufficient numbers are
available. That multimeter is so inexpensive and required for
future hardware work. Get the meter to make numbers
available.

I think you misunderstood the problem. I have a multimeter. The site you
gave seems to show how to test the power supply "out of context" - i.e. with
only a resistor hooked up to it, not an actual system. I don't see how this
test is at all useful for determining how the PS operates under an actual
system load, only in determining if the PS is faulty or not, and can supply
the rated *voltages* on the various output lines, not the rated *wattage*
into an actual working system.

 

[Eric]

Ok,
Thx! I will see what to do.

Eric

 

[w_tom]

The only part of that website relevant here is the wire
color, voltage, and limits. One need not test a power supply
outside the case. The system itself makes a better load. In
your case, the system would be a maximum load for that supply
- a better test.

I forgot about all that text associate with the chart. The
chart is then important data. BTW, the critical voltages are
+3.3, +5, and +12. Also a separate +5V backup voltage exists

 

[jeffc]

The only part of that website relevant here is the wire
color, voltage, and limits. One need not test a power supply
outside the case. The system itself makes a better load. In
your case, the system would be a maximum load for that supply
- a better test.

OK thanks.

 

[Gary W. Swearingen]

I think you misunderstood the problem. I have a multimeter. The site you
gave seems to show how to test the power supply "out of context" - i.e. with

The site also suggests dissipating 15+ W with a 10W resistor.