Help with pundit slow spinning replacement cpu fan?

Control: management of fans, temp/rpm monitoring via soft/hardware

Moderators: NeilBlanchard, Ralf Hutter, sthayashi, Lawrence Lee

Post Reply
Posts: 15
Joined: Thu Mar 10, 2005 11:11 am

Help with pundit slow spinning replacement cpu fan?

Post by jstyles » Tue Mar 15, 2005 7:05 am

Does anyone now why the Vantec Stealth 80x25 fan would spin at 600 RPMs at the same temp range when the standard Asus 70x15 fan in the pundit-r system runs at 2000RPMs? I am using the 3 wire cpu fan connector on the MB, with the case open.

I also tried leaving the Asus fan on the CPU connector and just hooking the Vantec Stealth on the 3 wire Case fan connector it still only spins at 600 RPMs. It is very quite which is what I wanted, but I am concerned that the Florida Summer will push the temps up to much.

Asus Fan 12V, .7A, 2000RPMs 40 CPU, 48 MB
Vantec Stealth 12V, .1A, 600RPMs, 47 CPU, 48 MB

I have a Panaflo FBA08A12L, but it doesn't show RPMs and I haven't check what the temp range is with it yet.

I have read where others have changed the fan or used software to slow down their fans, but I would like to speed this one up a little bit while still using the MB cpu fan power connector. Should I disable Q-Fan? Is the .7Amps to .1Amps difference what is causing the slow spinning?

I saw where someone reported that a previous BIOS version would allow setting the fan voltage, but not sure which BIOS version that was and if it will work with the rest of components in my system. I am currently on 1004

Thanks for any help.

ASUS Pundit-R
Pentium 2.4C HT
Kingston HyperX 256x2
Maxtor DM10 PATA 300GB
NEC 3520 DVD
Dvico Fusion 3

Posts: 1424
Joined: Sun Dec 12, 2004 5:00 am
Location: New York, NY

slow fan

Post by frankgehry » Tue Mar 15, 2005 7:24 am


What is the top speed of the vantec? Its 2150 rpm. 600 seems very slow but the vantec is not especially fast for an 80mm fan so its possible that the Qfan software is reducing the vantec to 600 and the orig. fan to 2000. I don't know if 80mm fans run at 4000 rpm, but I think so.

I like qfan alot especially for the cpu fan, so I would go into the bios and set the fan speed ratio to 90% and see if it runs any faster. You may have it set to 60% in which case it would be kind of slow.

The speeds that you list at the bottom are not at 12v are they? Those are the speeds that they run at through Qfan.

One other thing you can try is to turn of Qfan. If the fan runs faster you'll know that Qfan is slowing it down. - FG

Posts: 15
Joined: Thu Mar 10, 2005 11:11 am


Post by jstyles » Tue Mar 15, 2005 9:06 am

The BIOS version 1004 only lets you enable or disable Q-Fan, there is no settings for the fan percentage, unless you know of a different BIOS version that provides this for pundit-R

Thanks for your suggestions?

I will test without Q-Fan and see what that does as well.

I am concerned that the CPU_Fan power port on the motherboard is configured to work with .7A fans and that anything else will require more power than the MB can provide?

Posts: 15
Joined: Thu Mar 10, 2005 11:11 am


Post by jstyles » Tue Mar 15, 2005 11:05 am

I disabled Q-Fan in the bios rebooted and then the Vantec fan ran at full speed 1950 RPMs.

I used Speedfan to adjust it down to less noisy speed. After that I flashed the bios to 1002 and then had the option to set the start voltage, start temp and full speed temp in the bios, but it did not seem to work as well as speedfan.

I plan to test the stock fan, with no Q-Fan and adjust with speedfan. I am afraid that I will not see much improvement between the stock fan noise level and the Vantec or Panaflo, but this has been educational if nothing else.

Panaflo 75% SpeedFan, CPU 35, MB 42

Posts: 15
Joined: Thu Mar 10, 2005 11:11 am

Further Testing

Post by jstyles » Fri Mar 25, 2005 7:18 am

Trying to get better cooling, I have recently tried the panaflo H1B fans.

Replacing both the CPU and PowerSupply fans with two of the H1B. They seem to be able to cool a little better than the stock fans, but not worth the work required to get them to fit.

I had read where some people got better cooling by having the fan blow out instead of in on the CPU, but I have not been able to see that.

Running the H1Bs at 60% speed seems to keep the CPU and MB at 40C at idle and 85% at full load keeps it at 45C.

Post Reply