Advice needed on picking a truly silent PSU

zhenya · Post by **zhenya** » Fri Dec 23, 2005 8:35 am

Hey all,
I’ve been working on quieting my system in increments over the last year or so, and while it is now nearly silent by most standards, I’d like to take it to the next level. I’m still running an old 1.4 ghz Celeron based system, which is realistically good enough for my needs right now, and has the added benefit of being easy to cool passively! I recently purchased a P150 case, which is fantastic, but unfortunately the Neo 430 isn’t compatible with my Soyo motherboard. I’ve already RMA’ed it and the new one doesn’t work either. My system is very, very quiet right now, as the only fans I have are the rear fan inside my Antec Smarpower 2.0 350 PSU I’m using right now, and a 120mm Antec set to ‘low’ (and soon to be replaced by an undervolted, soft mounted Nexus.) Other than that the only other noise from the PC is my suspension mounted 80gb Spinpoint drive, which is still below the noise floor of the fans.

Anyhow, in my experimentation with different products, I often have found that a new ‘quiet’ product is actually louder than what I was replacing. With something as expensive as a good PSU, I’d like to minimize the chance of that happening (being as loud as my current PSU), and move towards the goal of hearing no difference when I turn my machine off.

With that said, I could use some advice as to where to go. I have been thinking obviously of a fanless PSU, as my low power system should have no trouble with one of these – however, I’m not sure of the Phantom 350, both because of the incompatibility of my system with the Neo 430 and the history of problems with this PSU. My next thought was the Silverstone st30nf, which seems PERFECT for me right now, but I imagine I’ll be forced to upgrade my system in the next year or so, and the Silverstone does not support PCI express as I understand it. Lastly I’m considering the Nexus NX 4090, but I’m worried that the fan noise will still be the predominant noise from my system. Thoughts? Any other options I’m not considering yet? Much appreciated!

Post by **MikeC** » Fri Dec 23, 2005 9:00 am

Chances are, the reason for the NeoHE PSU not working with your motherboard is its ATX12V v2.xx compliance. Your system is old enough that its current draw on the AUX12V might not be high enough; I know that this is a source of some incompatibilities between PSUs that comply with the latest ATX12V specs and older motherboards. In any case, check that PSU with another system if you can, and don't throw it out quite yet!

Considering the rest of your system, I'd say go ahead with the Silverstone fanless PSU. By the time you want to upgrade, you will want to upgrade the whole system anyway, and it's easier to leave this one intact, because it will probably still be useful and have value for someone else, perhaps.

You could also do something like a fan swap in your existing Smartpower PSU, but maybe you're not into that. A Panaflo 80 medium speed fan will be perfect for it and make it about as quiet as any PSU w/a fan. A lot cheaper than a Silverstone PSU and almost but not quite silent.

Also, before you replace the 120mm Antec fan, try softmounting it. The improvement is audible.

zhenya · Post by **zhenya** » Fri Dec 23, 2005 9:19 am

Chances are, the reason for the NeoHE PSU not working with your motherboard is its ATX12V v2.xx compliance. Your system is old enough that its current draw on the AUX12V might not be high enough; I know that this is a source of some incompatibilities between PSUs that comply with the latest ATX12V specs and older motherboards. In any case, check that PSU with another system if you can, and don't throw it out quite yet!

After getting my 2nd unit I talked to Antec about it and they said that it was probably because of the lack of -5v on pin 18 of their new PSU's. However, why then does my SP 350 unit, which is also v2.xx and lacks the same -5v pin work just fine? Anyhow, I'm not going to throw it out, I might try to sell it, or just hold on to it for when I upgrade my system.

Considering the rest of your system, I'd say go ahead with the Silverstone fanless PSU. By the time you want to upgrade, you will want to upgrade the whole system anyway, and it's easier to leave this one intact, because it will probably still be useful and have value for someone else, perhaps.

This might be a good plan, although because I'm having to restrain myself from upgrading already, I'd rather not buy a PSU that won't be compatible with my next system. I'd much, much rather buy one that can go seamlessly into my next system, and last me another 3-6 years.

You could also do something like a fan swap in your existing Smartpower PSU, but maybe you're not into that. A Panaflo 80 medium speed fan will be perfect for it and make it about as quiet as any PSU w/a fan. A lot cheaper than a Silverstone PSU and almost but not quite silent.

I've considered this, and have a quiet 80mm Papst fan that I was going to use, however the rear fan that needs replacing is a slim form factor. I have not run into silent fans of this sort (although I haven't looked too hard either).

Also, before you replace the 120mm Antec fan, try softmounting it. The improvement is audible.

It already is, and it is quieter than my PSU. However I already have a Nexus fan - this was one of the 'upgrades' that was actually a 'downgrade.' It also taught me that my system was quieter than I supposed (considering a supposed 22.8 dB(a) fan was considerably the loudest thing in my system).

Thanks for the input. Perhaps the Phantom 350 is the way for me to go. Does anyone have any input on the Nexus NX 4090 (which is rated at 16.2 dB(a)?) How truly silent is that?

Post by **MikeC** » Fri Dec 23, 2005 9:49 am

zhenya wrote:Thanks for the input. Perhaps the Phantom 350 is the way for me to go. Does anyone have any input on the Nexus NX 4090 (which is rated at 16.2 dB(a)?) How truly silent is that?

Forget about the Nexus PSU -- it ramps up too fast, will only be quiet if the intake temp can be kept really low. The Phantom is quieter --- but they are sometimes buzzy.... which the Silvertone (2 samples) never have been for me. This is at a pretty low noise level, but if you system is already that quiet, it might be a factor.

Also, about the SP2's 2nd fan -- just take it out is what I'd do -- unless it never turns on, in which case, leave it, obviously. Creating a front intake duct for the PSU would ensure adequate cooling.

Bar81 · Post by **Bar81** » Sat Dec 24, 2005 2:56 am

zhenya wrote:My next thought was the Silverstone st30nf, which seems PERFECT for me right now, but I imagine I’ll be forced to upgrade my system in the next year or so, and the Silverstone does not support PCI express as I understand it.

I don't know where you got that impression. As my sig clearly shows it support PCI-E and in a big way. It has a 6 pin PCI-E connector straight off the PSU and is doing an admirable job powering my X1800 XL at XT speeds. No coil hum, etc. Just the best PSU I have ever had the pleasure to use and the really nice thing is when they say 300W they really mean 300W unlike almost every PSU out there. I'm still pleasantly suprised it can run my rig with the dual core opteron at 2.5Ghz, the RAM at 250mhz, the three hard drives, burner, and oc'd vid card without breaking a sweat. I can't say enough, Silverstone really took care of business on this one.

blackstar · Post by **blackstar** » Sat Dec 24, 2005 4:11 am

"I have been thinking obviously of a fanless PSU, as my low power system should have no trouble with one of these"

im having a lot of luck with a fanless silentmaxx 350.. altho there have been reports of these units dying, its run so far for the last 8 months:
3200+ venice
2GB Ram
X800XL
spinpoint 160
AN8 ultra
1 x 120mm nexus fan @ 5v
ac cooling freezer 64 @ 5v

in a lian li v1000 (psu is bottom mounted, which i think is a much better layout for a fanless PSU in an air cooled system). im quite suprised that low rated PSU runs it all at decent temps.

next thing im going to try and do is duct the nexus case fan to the CPU cooler and try and remove one fan.

zhenya · Post by **zhenya** » Sat Dec 24, 2005 7:18 am

Bar81 wrote:
zhenya wrote:My next thought was the Silverstone st30nf, which seems PERFECT for me right now, but I imagine I’ll be forced to upgrade my system in the next year or so, and the Silverstone does not support PCI express as I understand it.
I don't know where you got that impression. As my sig clearly shows it support PCI-E and in a big way. It has a 6 pin PCI-E connector straight off the PSU and is doing an admirable job powering my X1800 XL at XT speeds. No coil hum, etc. Just the best PSU I have ever had the pleasure to use and the really nice thing is when they say 300W they really mean 300W unlike almost every PSU out there. I'm still pleasantly suprised it can run my rig with the dual core opteron at 2.5Ghz, the RAM at 250mhz, the three hard drives, burner, and oc'd vid card without breaking a sweat. I can't say enough, Silverstone really took care of business on this one.

Hmm, SPCR's own review http://www.silentpcreview.com/article185-page1.html
notes on the first page that it is not PCI-E compliant. Was the unit updated since that review? Anyhow, if that's the case, I'll definitely move the Silverstone back to the top of my list. Any recommendations as to where to purchase one? Thanks!

Post by **MikeC** » Sat Dec 24, 2005 9:35 am

zhenya --

If you include your LOCATION in your acc details, people can help you better -- about where to buy stuff.

Bar81 · Post by **Bar81** » Sat Dec 24, 2005 6:41 pm

zhenya wrote:
Bar81 wrote:
zhenya wrote:My next thought was the Silverstone st30nf, which seems PERFECT for me right now, but I imagine I’ll be forced to upgrade my system in the next year or so, and the Silverstone does not support PCI express as I understand it.
I don't know where you got that impression. As my sig clearly shows it support PCI-E and in a big way. It has a 6 pin PCI-E connector straight off the PSU and is doing an admirable job powering my X1800 XL at XT speeds. No coil hum, etc. Just the best PSU I have ever had the pleasure to use and the really nice thing is when they say 300W they really mean 300W unlike almost every PSU out there. I'm still pleasantly suprised it can run my rig with the dual core opteron at 2.5Ghz, the RAM at 250mhz, the three hard drives, burner, and oc'd vid card without breaking a sweat. I can't say enough, Silverstone really took care of business on this one.
Hmm, SPCR's own review http://www.silentpcreview.com/article185-page1.html
notes on the first page that it is not PCI-E compliant. Was the unit updated since that review? Anyhow, if that's the case, I'll definitely move the Silverstone back to the top of my list. Any recommendations as to where to purchase one? Thanks!

Well, either I'm on some serious drugs or they have updated the unit

It now has a 6pin PCI-E connector or at least I got one that magically has such a connector. The cable has a huge wrap around sticker with the PCI-E logo all over it.

I got mine here, lowest price to be found:

http://www.sharkacomputers.com/sissfaposu.html

Even if you get an older one without the PCI-E cable all you have to do is use one of these and magically you can support high end PCI-E cards:
http://www.svc.com/pcie-converter.html

I suggest you not read the reviews as gospel. I think you read the spc review comment too literally. It simply meant the PSU doesn't support PCI-E out of the box, but as I've shown that doesn't mean it can't.

zhenya · Post by **zhenya** » Mon Dec 26, 2005 7:21 am

Very cool. Sounds like the Silverstone is the PSU for me! Thanks for the help.

Bar81 · Post by **Bar81** » Mon Dec 26, 2005 7:46 am

np, enjoy