Legit Reviews

I have a recent Powmax LP8800-C psu that states on the box "supports fan speed monitoring".

It is an ATX 350W that "complies with ATX ver 2.03 and ATX ver 1.1"

The fan inside is the psu is also a Powmax, a 2-wire FM802512M, DC12V, 0.15A, Brushless, 0209, soldered to the psu board in the box.

The psu only has a 4-pin and a 20-pin connector, besides the molex connectors that supply the power to the devices .

Where would the rpm monitoring information come from, if it indeed does, and how is it transmitted to the mobo? (The 4-pin or 20-pin connectors are the only options as far as I can tell)

This is the reason I ask:

I have researched cooling for the new P4 system I am building, upgrading from my P3. My current P3 now is without a 4-pin connector, so I just have the 20-pin to connect which is req'd. So I do not know how the fan speed monitoring of my psu would work, if it does. Is the signal through the 4-pin 12V, or the 20-pin connector on my new P4C800E-Deluxe mobo?

I want to remove the supplied stock fan in the psu and replace it with a Vantec Stealth to match the 2 others in the case for intake and exhaust. It is quiet. It definetely allows fan speed monitoring, if connected directly to the 3-pin PWR_FAN header/connector I have on my new P4C800E-Deluxe mobo.

I would like to know first how the rpm is transmitted, ie through what cable.

Secondly, is it possible that the rpm is calculated on the psu board (by voltage or something?

Because I want to disconnect the current 2-wire fan out of psu that states supports fan speed monitoring!? and replace it with the Stealth by plugging it into the 3-pin PWR_FAN.

Would this cause any malfunction in the psu, and/or would a faulty rpm psu fan rpm signal be sent to the mobo, which would cause a faulty reading, even if I had the 3-pin PWR_FAN mobo header/connector attached directly to the fan?

As a last resort, I would re-solder the Stealth onto the psu with 2-wires like the stock Powmax fan. Then possibly try to connect the rpm signal wire only to the 3-pin PWR_FAN mobo header/connector, which would be a bonus. getting the right rpm reading, if any would be a bonus too I think, but I will have this fan, and quiet IS my goal.

I need to know PDQ because I'll be shopping in a dozen hours

I have not heard of the rpm signal going through the 20 or 4 pin mobo connectors before.

On my Thermaltake Purepower 360W PSU, there is a single wire coming out of the PSU that plugs on to your motherboard's 3-pin connector. That is the only way I have heard of PSU rpm monitoring.

Anyone else have input?

I bought three Vantec Stealth 80mm 3-pin rpm monitorable fans: to refit my psu fan with 3-wires to the mobo (which is now rpm monitored); replace my 4-pin rear exhaust non-rpm monitored fan (as 4-pin non-rpm monitored); and add a front intake fan (rpm monitored). Stealths are 12V, 21dB, 1.2W, 2050rpm, 27cfm, double ball bearing. Stealths are quiet and well reviewed, and for the lowest noise are relatively pretty powerful.

I now have all the available ASUS x_FAN 3-pin connectors filled (includes cpu fan) to give me rpm monitoring of all 3, and I already had cpu and mobo temp monitoring.

I happened to have Motherboard Monitor 5 software installed, which nicely gives the mobo and cpu temp readouts directly in the systray. It also has a readout (now at zero) for a third temp monitor-surprise: there is a "TRPWR (designated as a power supply thermal connector....if ps has a thermal monitoring feature", Asus. I suppose if things are gonna heat up in the psu or elsewhere I could install a thermisor (or whatever you call it anywhere I want).

I don't know if there is any way to have 3 fan speeds listed in the systray also. - ANY ANSWERS HERE?

The 3 fan speeds are varied by current/average/min/max by up tp about 5% each (after 1 hr.), and the Stealths aren't the exact same.

I have dropped a few degrees C overall (not nec'y on cpu) by the looks of it. The overall noise is only slightly lower than it was before with a cheesy rear exhaust 4-pin, and stock psu fan, and cpu fan to compare with. But I also did not have any front intake before. If anything it is just repaced by a midrange deeper (better) drone. I am confident that I now have more efficient air flow, and if I need more I will put one intake Stealth on the side, and maybe another exhaust Stealth on the top. I can leave the real work up to a quiet cpu cooler, as I believe any extra benefits of having high rpm fans are outweighed by the lack of any real accurate control worthwhile (automated) control system, but mainly because of NOISE - I'll see.

Now I know you can get tiny rubber edging at hardware stores I 'm gonna cut holes in my case for plexy and more fans.

It occurs to me that mbm5 software does as much and more as ASUS and that hardware should be bought for purpose and not to comply with any software, which was my original concern.

currently ASUS cusl2-c, soon p4c800e-deluxe.


Thanks to all.