(8RDA3+) Voltage readings.....

[Blackmyst]

Hi.

I recently got my hands on a multi-meter, and tested my rails. I'm ot sure if I did it right, so bare with me. I measured on a spare molex. I'm just not sure which ones to measure.

I "think" I did it right, and here's what I got:

12v RAIL = 12.18v

5V RAIL = 5.14v

Does this sound right? MBM reports these as:

12V RAIL = 11.6v

5V RAIL = 5v exactly.

Is MBM normally this far off? The BIOS reports similar voltages as MBM. Is this why I suffer from an undervolting CPU supply?

Blackmyst

[Veky]

Have you set the Voltage Configuration to 8RDA3+ in MBM?

[Blackmyst]

Didn't realise I could do that - how do I?

Blackmyst

[phiphen]

what configuration do you use veky?

[Veky]

The latest MBM version 5.3.4.0 has the 8RDA3+ voltage config. It's under settings -> voltages -> voltage configurations.
I believe it showes the voltages a little more accurate and the -12V is now shown correctly. Looks like it's VAGP since it's showing 1.55V. (it showed -6V before)

Oh, I have one other tip too, in the voltages, add two more sensors and you get the 5V SB and VBat.

NF7 is supported aswell.

[hchu]

I have an Antec TruePower 430W but my 8RDA+ shows the 5V line as 4.93-4.97V and the 12V line as 11.85-11.91V. However the VDIMM is much more stable at 2.86V. Hope this helps allieve any concern about voltage readings, I myself trust my Antec more than my 8RDA+.

[Veky]

Originally Posted by hchu

I have an Antec TruePower 430W but my 8RDA+ shows the 5V line as 4.93-4.97V and the 12V line as 11.85-11.91V. However the VDIMM is much more stable at 2.86V. Hope this helps allieve any concern about voltage readings, I myself trust my Antec more than my 8RDA+.

+- 5% is still tolerable.

[Veky]

BTW, here are my voltages, I think they're decent.

8RDA3+ 1.1 and Enermax 350W here.

http://www.inet.hr/~srjurak/usdm.gif

[Áedán]

Basically, the chip that reads the environmental settings isn't really that accurate. As there's only one of these chips onboard the motherboard, all software uses the same chip to read the voltages. Hence, it's not surprising you see the same results in UDSM, MBM or the BIOS, as these are all reading the same values from the same chip.

If the chip doesn't measure accurately, then all software tools will give you an inaccurate answer.

For the 5V rail, I tend to measure across the IR header, as it's on the other side of the board from the power connector.

For the 12V rail, it might be better to measure it on the board (somewhere in the CPU regulator section...) to find out how it actually looks.

Most current boards appear (from experiences of others and myself) to read the voltage lower than it actually is. Some boards seem to deviate more, but I'm not sure if this is the result of inaccuracies in the enviromental monitor itself, or the resistor dividers.