Quick question about my PSU.

[Teekz]

Hello, all.

Right, I only have a 400W PSU at the minute, and I fear this is not enough to properly power my machine. I intend to buy a new one at 750W some time soon, but I wonder if there is a way to determine if my current PSU is a little too weak for my system?

I have attached a snip of SpeedFan's power section, in case that could be an indicator.

Cheers,
Tom.

 

[Dwarf]

Those voltages don't look right. The +5V lines are well out of spec. What figures do you get on the appropriate page in the BIOS?

The voltages should lie within the following ranges (we can ignore the negative rails, as these are not used any more):

Loose Tolerance -10%/+8%:

3.3V 2.97V / 3.63V
5.0V 4.5V / 5.4V
12.0V 10.8V / 12.9V

Tight Tolerance -5%/+5%

3.3V 3.135V / 3.465V
5.0V 4.75V / 5.25V
12.0V 11.4V / 12.6V

Your +5V line is reporting a deviation from the nominal level of +37% in the first column and -28% in the second, both figures are well out of the tolerance ranges.

 

[Ivan the SoSo]

the 5 volts out of spec but here it is...eXtreme Power Supply Calculator
I use 996 watts....

 

[Teekz]

Well, assuming I entered everything correctly, I got "Minimum PSU Wattage: 385W", and "Recommended PSU Wattage: 435W", but I added 40% aging to be safe, since my machine is on a lot. Based on this, I think my new 750W should do the trick, once I actually buy it.

A few questions, if you don't mind.

- Is it possible to damage my system by installing a PSU that is too powerful, or is it regulated somehow?
- What does it mean that my tolerance ranges are out by quite a bit? Should I be concerned?

I'll reboot and check the BIOS power values now, and report back with them in a moment.

 

[Teekz]

I have the BIOS values.

Vcore = 1.326V
DDR2 1.8V = 1.856V
+3.3V = 3.392V
+12V = 12.302V

 

[Ivan the SoSo]

No.... I'm running 1260 watts with dual PSU's

The voltage has a range that is acceptable... ie... +/-10% of 5.00 volts is .5 volts so 4.5-5.5 volts is good...your running 3.60-6.85 way out of range

Yes...one your at the limit of the power supply...two the 5 volts unstable....

 

[Teekz]

I shall make it a priority to upgrade my PSU as soon as possible, then. I plan to buy a 750W one, made by my local computer shop, is there any chance you could verify that it will be suitable for the job?

I intend to buy this.

 

[Dwarf]

Well, assuming I entered everything correctly, I got "Minimum PSU Wattage: 385W", and "Recommended PSU Wattage: 435W", but I added 40% aging to be safe, since my machine is on a lot. Based on this, I think my new 750W should do the trick, once I actually buy it.

A few questions, if you don't mind.

- Is it possible to damage my system by installing a PSU that is too powerful, or is it regulated somehow?
- What does it mean that my tolerance ranges are out by quite a bit? Should I be concerned?

I'll reboot and check the BIOS power values now, and report back with them in a moment.

You cannot damage a system by installing a PSU with greater capacity than your system requires, and this will also give room for further expansion as well as running cooler/more efficiently.

Voltage tolerances are very important, because dropping below the limits can cause malfunctioning and exceeding the limits can actually damage your hardware.

I have the BIOS values.

Vcore = 1.326V
DDR2 1.8V = 1.856V
+3.3V = 3.392V
+12V = 12.302V

Those figures look fine, but what about the +5V rail as this is the one that is out of spec?

It could well be that there is nothing wrong with the +5V rail, other than the value being incorrectly reported by SpeedFan. I think that is probably the case, since a +5V rail that far out of spec will prevent your system from running at all.

 

[Ivan the SoSo]

I shall make it a priority to upgrade my PSU as soon as possible, then. I plan to buy a 750W one, made by my local computer shop, is there any chance you could verify that it will be suitable for the job?

I intend to buy this.

It should be, but I can't vouch for the company....

 

[Teekz]

Those figures look fine, but what about the +5V rail as this is the one that is out of spec?

It could well be that there is nothing wrong with the +5V rail, other than the value being incorrectly reported by SpeedFan. I think that is probably the case, since a +5V rail that far out of spec will prevent your system from running at all.

There was no +5V value in my BIOS, I was slightly confused, as I expected one.

Still, I think this one will do, until I buy my new one. I think the store re-opens on January 4th, so I'll probably buy one around that time.

Thanks for the help.