I'm a little upset right now. I shelled out 350$ for a shuttle SB75S Limited Edition box with the silentX psu thinking it would be the quietest thing that I could get without going overboard. when I got the box, it wasnt the same silent x external psu that was included in the review of another shuttle system done by silent pc review, it was an internal PSU that has 2 small fans that are speed controlled. after I put the system together and fired it up, I noticed that the psu fans are by far the loudest thing in the case by far. when I tried stopping one, the other started reving up and down and that just drove me nuts. my question; is this the right PSU? is it supposed to be this loud? would it not be smart to stop both of the PSU fans?

thanks

WELCOME TO SPCR

Sorry to hear that the SilentX PSU is really loud. I've been debating getting this PSU for months. Yes, what you have IS the SilentX power supply with 2 fans. The normal power supplies only have 1, and I can tell you that they're REALLY loud (I'm sitting next to one right now ). What's on the Shuttle Zen with the external passive power supply is NOT the SilentX whatsoever. That's unique only to the Zen.

I don't think it would be smart to stop both PSU fans, since those fans are there to disippate heat from the power supply. Although you could probably stop both temporarily to see if that's truly the source of your noise.

I did stop them for a sec to see if that was it. they are by far the loudest fans in the case. I tried to stop just one, but then the other starts pulsing and that drives me even more nuts

supraopticus --

If you bought this Shuttle by mistake, why don't you see if the retailer will swap it for the one you wanted in the first place?

I bought it direct from shuttle. what I'm going to try is to open up the psu and put an 80mm fan inside the case blowing on it and kill the two smaller fans

Not sure if that's wise. Before you do this, what are the components in your system?

p4 2.8c
1gb DDR400
ati AIW 9600 (fanless model)
2 WD 36gb sata raptor drives
pioneer ao3 dvd-r

I opened up the psu, the 2 fans are connected via plugs so I unplugged both just to see what happens. the psu has a temp sensor that shut it down soon after. then I tried running 1 fan, it helps, but the fan is still loud so I connected it to a standard fan header on the mobo and tried to use speed fan to slow it down more. its still the loudest thing in the case. I'm thinking I'm going to buy different fans (slower speed) and mount those to see what happens. any suggestions for some good quiet 40mm fans

I can't believe that you're running to 10krpm drives in there. I have been advised against a single one because of the heat.
Are the drives getting really hot? If so, that could be what's causing the system fan to run really fast.

supraopticus --

Chances are, your components are drawing enough power & generating enough heat to push the thermals in that PSU beyond the fan ramp-up point and keep it there. I don't think you are going to succeed in making the PSu run quieter safely without some really major work.

To test my theory, just try undervolting/underclocking your CPU, and minimizing the # of components -- ie, one drive, 256mb ram.

You might get some gains by cutting away the CPU fan exhaust grill. More efficient evacuation of heat from the system by this larger fan should lead to lower PSU fan speed.

Bottom line: The box is too small for the amount of heat in it.

I've already begun to work on replacing the fans. the fans arent ramping b/c they are the same volume from startup to shutdown. I'm not sure, but I think these fans are pretty high RPM fans. when I connect them to the MB and use speedfan to slow them down, they are still spinning pretty fast and have this horrible whine. I'm currently looking for 40mm fans with lower rpms. right now I just have 1 psu fan plugged in and its still bad. when i cut that fan, my case goes from this high pitch to a nice low hum

That's strange. I have the 250W SilentX PSU and it is very quiet. Almost no noise at all. It's called silent X because that's what it is, silent... maybe you should just return it.

I bought the Silent X PSU for my SS51G, but I am not especially impressed. It actually sounds slightly more annoying than the old one. If anyone has modded it I'd like to know about it.

Frode,
Noway

The SilentX in my rig is far from silent. It is fine when I first fire it up, but it quickly becomes annoying as it heats up.
The SilentX 250w is quieter than the unmoddified 200w unit that came in my origional SN41G2. The SilentX is quite a bit louder than the same 200w unit that I modded with an ADDA 0412MS-G70 fan, it was silent and completely stable. I am considering switching back to the 200w with a fan mod, and selling my 250w.