New low noise! PSU - how big should it be?

petal · Post by **petal** » Mon Apr 28, 2003 1:53 pm

Ok I'm about to upgrade my system to make it as low-noise as possible, before I go crazy. At the moment there's only two fan's in my system. One on the CPU (Glacialtech Iglo) and a Pabst 19dB in the cheap 250W PSU that i've got - but it is still making a lot of noise!? The third noisemaker is my damned IBM deskstar HDD, which works well, but it "sings" with a highfrequent very unpleasant noise.
Anyways I have decided to make the upgrade in small steps:
1. PSU
2. Cabinet (Noise Control Big ATX with Magic Fleece)
3. New Mobo + CPU + RAM
4. S-ATA HDD (Low-Noise)

As some of you can see, this is not a low-cost project, and the Mobo upgrade want take place within the next year or so.
But the PSU is next. My only problem is that I don't know how big it should be, in order to have enough power for the future upgrades that I am planing. My friend tells me to get a 400W PSU - In the store they tell me that a good quality 300W PSU will do just fine (and it is half the price). So what is your opinion and experience on this topic? It would be of great help if you could give me some guidelines regarding how big this new PSU should be, and also if you could point out qulity PSU-makers, and which to avoid at all costs.

Cheers!
Thomas

aMo · Post by **aMo** » Mon Apr 28, 2003 2:25 pm

I don't know much about making the perfect low-noise pc, I have 6 fans altogether in my Lian Li cabinet (2 in front sucking air in, 1 in the back blowing out, one sucking air into the psu and one blowing out, and a low-noise Glacialtech cooler.
It all makes noise, mostly air-flow noise, but I don't really mind..

However, I do know that if a silent harddrive is what you want, there is no substitute for Seagate HDD's.
They aren't the fastest disk's on the market, but they are the quietest ones.

Immanuel · Post by **Immanuel** » Mon Apr 28, 2003 4:59 pm

Yes, if your hard drive is the biggest annoyance, the Baracuda V series from Seagate is absolutely the quitest drive you can get. For an indebth test, go to http://www.storagereview.com

Don't believe Pabst. They are so full of lies. Technically probably they do not lie. I believe their fans do make very little noise in a "dead" room at 1meters distance and hung up in free air. But that is not a real life situation. I have had 5 or 6 of their 12dB model in my hands. When hold up in the air, they are virtually noiseless. But their skeleton is fragile - or in other words ... the whole thing will start vibrating multiplying the noise quite a bit, if you i.e. put it on a table.

But you asked for advice on a PSU. PC PSUs do have a weakness, that most people do not know. If they get hot, they will drop severely in efficiency. I found out about that, once I went to Enermax homepage to get some PSU specifications. They actually told, about the output at different temperatures. Just taking any PSU and giving it a low noise (wich most often means inefficient) fan MAY lower the power of the PSU.

There is quite a bit of difference in PSUs. I believeit it IS true, that 300W quality is better than 400W crap. For some more reading on PSUs (with a lot of graffics), you can go to http://www.tomshardware.com They have a megatest of PSUs somewhere. As far as I remember, they even have a little allround info on the subject too.

Nestor · Post by **Nestor** » Mon Apr 28, 2003 7:12 pm

By a logical matching thing, your PSU shoud be matched by your PSU unit.

Nestor · Post by **Nestor** » Mon Apr 28, 2003 7:12 pm

By a logical matching thing, your PSU shoud be matched by the power of your computer.

<font size=-1>[ This Message was edited by: nestor on 2003-04-28 23:29 ]</font>

Spirit · Post by **Spirit** » Tue Apr 29, 2003 12:10 am

has anyone changed the power supply on their own PC ? Is it hard ? I've an Asus P4B266 mobo.

I've swapped CD drives, hard drives etc, but fiddling with electricity always make me a bit nervous.

jupiter8 · Post by **jupiter8** » Tue Apr 29, 2003 12:26 am

I have'nt changed PSU per se but i took mine out and put it in again.
It's no problem.
About as complicated as changing a CD drive but with more cables so it takes more time.

petal · Post by **petal** » Tue Apr 29, 2003 4:07 am

On 2003-04-28 20:12, Nestor wrote:
By a logical matching thing, your PSU shoud be matched by the power of your computer.

This is true (I guess) but I still need some clues about how much power a pc needs. As I don't plan to upgrade the mobo+cpu, I quess, that the kind of powercunsumption that my future pc is going to have, will be equivalent to what the most powerfull pc's have today, and then maybe a little bit more. And if I understand correctly, having enough powersupply, is crucial, if you wanna keep your system stable.

But thanks for the inputs so far, just keep'em coming my way....
Thomas

aMo · Post by **aMo** » Tue Apr 29, 2003 9:30 am

Well, remember that an AMD XP3000+ alone draws 85 watts from your psu during full load..

And most PSU's rate their power-output by peak output (The Enermax 550w psu actually only delivers 423w continously)..

I bought a pretty cheap 550w psu (Q-tech), and it actually outperforms an Enermax 550w psu (at least according to a test I read on a web-site somewhere, don't remember where)..
It's rated at 33db's of noise.. so it's not the quietest one out there, but still pretty good...

Immanuel · Post by **Immanuel** » Tue Apr 29, 2003 10:30 am

The quietest fast PC is the one on the other side of the wall - with cables going thru the wall, and the hole filled afterwards.

Nestor · Post by **Nestor** » Sat May 03, 2003 1:06 pm

Please, have a read choosing one of the powers you think you need:

http://www.antec-inc.com/pro_powerSupply.html

This new technology does not deceive you telling there is 550W when you just got 375W for instance, AND… one of the most important points is the division of power supply into the power supply unit itself… read on and learn it by yourself.

I’m going to go with a 430W TruePower and I’ve been told it’s a perfect match for those using for IDE drives like most of us do: two HDs, the CDRW and a CD read only.

Micha · Post by **Micha** » Mon May 05, 2003 5:11 am

Changing the PSU is easy. Just pull off the cables and unscrew the 4 screws surrounding the On/Off switch. New one in and backwards.
The 4 holes for the screws are only one way to use, the correct.
To recommend at the moment:
proSilence FANLESS 350
No fan, thus 0 dB noise. Sufficient for a normal setup. Maybe not to recommend for very warm countries. Also good is the Engelking (I got one last year: silent!).
Enermax also not bad, about 20 dB.

Immanuel · Post by **Immanuel** » Mon May 05, 2003 5:24 am

Creamware cards turn hot, and they need ventilation.

Micha · Post by **Micha** » Mon May 05, 2003 6:07 am

done by Verax. 12 dB.

Immanuel · Post by **Immanuel** » Mon May 05, 2003 7:04 pm

Not bad

How many DSPs do you use?
I had to turn up the noise (fans), when I added a Scope SRB

Micha · Post by **Micha** » Tue May 06, 2003 3:13 am

4 DSP. For cooling I use a very small Papst mounted at the end of the card (inside). So it is in the cooling stream from bottom, my "Air In" device, via Pulsar->AGP->CPU to "Air Out". So no need for help from PSU. Temp inside ~35 Celsius. Hottest item CPU with max ~40.
Verax has announced a case VX1 that seems to be very interesting. The airflow is from bottom to top. Could be a very good solution for Scopeboard users. I think it will have possibility to install at least 2 Air Out without the need to have a Air In. So one stream could be used "for DSP only".
Hopefully.

Immanuel · Post by **Immanuel** » Tue May 06, 2003 7:44 am

I prefer having "more air comming in, than comming out". I know, that is not realy possible, but having a bit of overpreasure in the PC prevents dust from "grabbing" the cirquits and other inportant places.

Micha · Post by **Micha** » Tue May 06, 2003 8:08 am

Yeah, that's why I hope the case has one In and two Out. That would be perfect.

Immanuel · Post by **Immanuel** » Tue May 06, 2003 8:13 am

I would prefer 2 in and 1 out.
I just works better

I don't know if it is because, the dust is heavyer than air, and therefor do not so easily get into the PC with over preasure?

Micha · Post by **Micha** » Tue May 06, 2003 9:09 am

Hmm, good point. 2 filtered Ins. Thanks, Immanuel.