AOpen SilentTEK: 6-week field report

Post by **MikeC** » Tue Apr 22, 2003 2:55 am

I have been meaning to do this for ages since posting the review on the SilentTEK fan speed / temp control system embedded in the AOpen AX4GE Max motherboard: a field report after actually using it in a system for several weeks. Because of the complexity of the software and its options, I think this is the only way you can get a really good handle on what exactly it can and can't do for you.

So here is my report after ~6 weeks of actual use in one (actually 2) system:

The system

AOpen AX4GE Max
P4-2.8 or P4-1.8 cooled by Thermalright 900 + Panaflo 80mm L @6-8V
512M DDRAM
2 Barracuda HDD
nVidia 9800 128M (w/Panaflo 80L @7~8V w/ fanmate1 controller on Zalman bracket) or integrated on-board video
Yamaha 44X CDRW
Seasonic 300W PSU/Panaflo M fan mod
2 Panaflo 80L case fans - 1 back, 1 front, 5-8V
1 Zalman fanmate 1 fan controller
Optimized airflow modded case/PSU - some damping.
Windows XP Pro (SP2)
24/7 Folding@home.

A. P4-2.8 + nVidia 9800: This system is tough to cool quietly, especially because it is constantly running Folding@home for the SPCR team. It is always at 100% load. My target is to keep the CPU temp under 60C and the case temp under 40C. In my current config, it ranges 55-60C for the CPU and 36-41C for the system.

With 24/7 Folding@home, it is too hot a system for the 2-fan control SilentTek (or SilentnBIOS) to handle. First, there are way too many fans. The fan for the nVidia 9800 VGA is connected to the third mobo fan header and set to a fixed voltage via a Zalman fanmate 1 fan controller. I found I cannot use any of the modes in which the fan modulates on/off or adjust speed with temperature -- even when the on voltage is very low, in my quiet office, the change in noise is easily, annoyingly heard. And with this hot system, the fans go on/off too often.

I found the best SilentTEK mode for this system was the fixed speed mode, set to the lowest. The only trouble there is that the minumum speed is sometimes too high, at ~6.5V for the CPU fan header and about 5.5V for the case fan header. Right now, I am running a splitter to run both the CPU fan and the back panel fan off the CPU mobo fan header. As the Panflos draw so little current, and because the highest I ever set the voltage to is ~8V, there is little danger of burning out the header. The front case fan is running at min (5.5V) on the 2nd SilentTEK controlled fan header.

What are the advantages of SilentTEK for this system as it is current configured?

Basically it saves using a fanmate1 controller on every fan - and there are 4 fans. Instead, I use only 1 fanmate1. The system is the loudest in my stable -- probably 24-25 dBA. Chances are I can't really get it lower without more case customization and/or better noise/airflow ratio fans becasue of the hot CPU and VGA. When the Folding@home is turned off, then it is feasible to use one of the fan-modulated options; I liked the result obtained with the Multiple Level control, although I used only 2 or 3 levels and it took a lot of experimentation to get it to behave exactly the way I wanted.

The worse thing about SilentTEK for me in this system is the cumbersome interface:
- it is easy to accidently close it, causing instant noise havoc
- can't be nicely reduced like MBM into the desktop tray, with shortcuts accessible there.

B. P4-1.8 + integrated VGA: It's a much cooler system, even running Folding@home 24/7. But the amount of heat generated still makes it impractical for me to leave it on any fan-modulated option, the change in noise is too annoying. But I reach the same target temps (or lower) as described above with all the fans set to their lowest via SlientTEK. The overall noise is 3-5 dBA lower than the above, and of course there is one less fan (the one on the NV9800). With Folding@home off, the system works well on any of the fan-modulated options if you choose good options. The integrated VGA is perfectly serviceable, even for photoshop and DTP work, btw.

In conclusion, the self-adjusting SilentTEK features work best when
-the system components are not super hot
-there is good airflow through the system, and around the CPU
Then the CPU fan can be set to trigger only when very hot and thus not ever trigger becasue the good case airflow keeps it under that temp. Yet there is no risk of CPU overheating.

The trick is to set the case fans to constant but quiet speed, which cannot be done by SilentTek if the CPU fan is auto-adjusted. So the best setup would then be fixed low voltage, quiet fan(s) for case airflow, maybe using fanmate1 controllers, a top CPU cooler and the CPU fan temp controlled by SilentTEK. Maximum airflow with minimum noise is still mandatory, but SilentTEK does make it all a bit more fun and "scientific". I am not quite as enthusiastic about it now that I see its limitations more clearly, but there still is nothing better in motherboard embedded temp/noise control.

JimK · Post by **JimK** » Tue Apr 22, 2003 4:34 pm

Mike,

It looks like the AOpen SilentTec is most useful in a "normal" situation where the load on the system varies over time. With the constant 100% load of Folding@Home you could probably tune the various fans with any of several standard pieces of hardware.

You are using an 80mm L on the Thermalright 900, how about a 92mm and have the overwash cool the Northbridge, etc.? Is there any benefit to the tach/speed output from the fans with the SilentTec sustem?

Jim

Post by **MikeC** » Tue Apr 22, 2003 4:48 pm

>>> It looks like the AOpen SilentTec is most useful in a "normal" situation where the load on the system varies over time. With the constant 100% load of Folding@Home you could probably tune the various fans with any of several standard pieces of hardware.
Yup, s'what I found. I think a nicely thought out multiple fan controller with locked fan speed settings would be best for a constant high load hot system. If this was a <20~25W CPU, I could probably go back to the auto-control settings.

>>>You are using an 80mm L on the Thermalright 900, how about a 92mm and have the overwash cool the Northbridge, etc.?
There is some overflow from the 80mm anyway, and the system is never even close to unstable, the NB HS doesn't feel that hot... Besides, I've never even seen a 92mm Panaflo.

Hard to believe but true

>>>Is there any benefit to the tach/speed output from the fans with the SilentTec sustem?
Yes there is, just can't remember exactly what -- actually I think the CPU fan right now is a 3-pin Panaflo M with tach output on min. ST setting. It's been a while since I've actually played with all the settings.

JimK · Post by **JimK** » Tue Apr 22, 2003 5:10 pm

Thanks Mike,

I was close to building a new Digital Darkroom with the AOpen AX4GE, Thermalright 900 on a 2.53 (good price point) in a Sonata case. Thought of a Panaflo 80 M BX to mod the Antec 380 PSU, the 92mm L BX for the HS and moving the stock 120mm fan to pull through the HDDs with a quieter 120 as exhaust. Run the 120s off the "fan only" leads and let the motherboard take care of the HSF. But I don't really "need" it yet so I will wait until early Summer and do something similar on the AOpen Springdale board (no Northbridge fan).

Having fun quieting my P II 300 email system, looking for a 333 with a passive HS on ebay right now. Then I will find out if the PSU is annoying enough to send $32 to Newegg for a Fortron 120mm PSU that will also help cool the CPU.

Jim

herosformula · Post by **herosformula** » Tue Apr 22, 2003 5:24 pm

Mike C, I am suprised to see that the 2.8 9800 combo runs so hot. With my 2.53 4600 combo, I never see a CPU more than +6c from chassis, right now with folding@home running it is 38c CPU 32c chassis.

Does it normally run that hot, or are you pushing the temps up by stagnating air flow?

Post by **MikeC** » Tue Apr 22, 2003 5:52 pm

herosformula -- it's what I get. 55-56C as I type on that machine right now. Case is at 37. CPU load is always 100%. (folding). It's actually undervolted salightly -- from 1.55V (?) down to 1.475V I think.

Airflow is excellent as vents are completely unimpeded -- everything cut away, bezel hole hugely enlarged, suck intake at bottom. The PSU has its own intake straight from the top CD drive slot which I've deliberately left empty. A 1/4" thick tunnel of closed cell foam leads from there to the intake of the Seasonic, whose grill is modded for very low impedance. So the PSu temp is unaffected by the rest of the components. It's a well-optimized airflow case.

Just paused folding; opened up side panel. Will leave off for 5 mins, replace, wait another 5, then see what happens to temps.............

OK.

CPU: 34, case: 35

I've turned folding back on & it is steadily climbing. Back up to 55, I am sure. I might not have used ArcticSilver3, maybe just grabbed whatever was around, that could have a small maybe 2C effect. The metal clips that comes with the T900 could be slightly suspect, as I found I had to bend it a bit to get it to fit nicely; trouble with bending is it bends back...