Hello, <BR> <BR>I changed my Dells PSU fan with a Zalman and it's very quiet. But I can hear a low hum coming from the power source is this normal? If it is normal do you know if the PSUs that are specifically made to be quiet like <!-- BBCode auto-link start --><a href="http://www.pcpowercooling.com" target="_blank">www.pcpowercooling.com</a><!-- BBCode auto-link end --> have this noise also? <BR> <BR>Thanks <BR>Shane
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you can stop the fan with your fingers. If the hum stops, the fan is the problem. <br> <br>If this is the case, try slowing down the rpm by connecting a 50-100 ohms 1Watt resistor to any wire of the fan. Or replace it with a quieter fan like panaflo FBA08A12L1A (USA) or papts8412NGL (Germany). <br> <br>Greetings from Spain.
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Jose's advice is sound. Fans do make a wide range of sounds. The same fan at different voltages /rpm can sound quite different. <br> <br>But if you have a 3-wire fan, that resistor should be added only to the red or black (sometimes blue) wire. The third wire is for rpm sensing only.
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Thanks for your advice guys. I stopped the fan and the hum is still there. It's coming from the side middle of the PSU. Could it be a capacitator or something? It's kind of like the sound from a monitor. I take it you don't get that sound with the fan stopped? <br> <br>Shane
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I see here that the noise is normal and from the electrical components. <br> <br><!-- BBCode Start --><A HREF="http://www.cocoon-culture.com/lib/noise-report/psu-2-investigation.htm" TARGET="_blank">PSU Silent</A><!-- BBCode End --> <br> <br> <br>I guess I have to live with it or incase the PSU in concrete and pour wax into it which I will probably not do.
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It sounds like your PSU is poor quality. I have some PSUs, and I can hear that humm at all. <br> <br>Try replacing it. Your hearing will be grateful. <IMG SRC="modules/phpBB_14/images/smiles/icon_wink.gif"> <br> <br>Regards.
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In my opinion the Zalman PSU is one of the best quality PSUs out there. It uses only the best parts which is evident by its weight, being much heavier than any other PSU I have picked up. Its also the quietest I've heard to date. Check out this review for a look inside... <br><!-- BBCode auto-link start --><a href="http://www.mikhailtech.com/articles/other/zalpsu300/" target="_blank">http://www.mikhailtech.com/articles/other/zalpsu300/</a><!-- BBCode auto-link end --> <br> <br>I'm pretty sure the hum you are experiencing is caused by the inductor in the PFC circuit. If too much current is drawn from the PSU the inductor in the PFC circuit will tremble. To fix this you will need to reduce the power drawn from the PSU. Zalman mentioned this a while ago on their support site. Remember it is a 300W power supply and not as big as some others. When building a quiet PC you should also consider the efficiency of the system and try to get it using as little power as possible. <br> <br>I suggest removing some parts from your system to reduce the power draw and see if that helps. <br> <br>
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>>I suggest removing some parts from your system to reduce the power draw and see if that helps. <br> <br>That's something I was just thinking about the thermally controlled PSUs. Would buying an "overkill" PSU for a system result in it running cooler and thus keeping it's thermally controlled fan speeds low? In my current system, P3-1000, 384MB RDRAM, 2x 40GB 7200RPM HD, DVD, CD-RW, GF256, 10/100 NIC, SB Live, I have a Delta PSU which IIRC is rated at 200W. <br> <br>I was in the store the other day and saw the Antec TruePower 430 and was thinking of picking it up as it has thermally controlled PSU and case fans with dedicated plugs. I was looking for a lower-power version as I figure the 430W is overkill, but drawing 180 watts from a 200W PSU would generate more heat than drawing 180W from a 400W PSU correct? I know my stereo's pre-amp and power-amp powersupplies get much warmer when I'm playing my stereo at loud levels, so I figure a PCs PSU should act similar.
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Re: the hot glue -- PSU makers use the stuff in the PSU for all kinds of things, so it's not such a stretch to try and dampen the coils with it. If you're going to replace the PSU anyway... <br> <br>Buying an "overkill" PSU for a system would not result in a cooler PSU. The key factor is the efficiency of the PSU. Usually around 70% -- this tells how much of the AC power is converted to DC output. 180W drawn from a 70% efficiency PSU means 77W sis lost -- as heat. This would not change if you went to a higher rated PSU unless the efficiency was better (as long as the first PSU is being used within spec). <br> <br>The other question is whether higher power PSUs have better internal cooling; the answer is not really, as far as i can see. Usually the 350W and 430W PSU in the same line have the same heatsinks. The fan(s) are overkill in the first place, so why bother with heatsinks if you're the manufacturer? It's the ratings of compnents such as capacitors, regulators, etc that is higher so they can handle higher loads. <br> <br>BTW, your system probably draws ~100W max. Not that this means you can get by with a 100W PSU... See <!-- BBCode Start --><A HREF="http://www.silentpcreview.com/modules.php?op=modload&name=phpBB_14&file=index&action=viewtopic&topic=21&7" TARGET="_blank">this thread </A><!-- BBCode End -->about PC power draw of different systems. <br> <br>Antec TruePower 430 -- not so quiet. See the comments by HYUM about his TruePower in <br><!-- BBCode Start --><A HREF="http://www.silentpcreview.com/modules.php?op=modload&name=phpBB_14&file=index&action=viewtopic&topic=20&start=15" TARGET="_blank">this thread</A><!-- BBCode End -->
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<!-- BBCode Quote Start --><TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font class="pn-sub">Quote:</font><HR></TD></TR><TR><TD><FONT class="pn-sub"><BLOCKQUOTE>Buying an "overkill" PSU for a system would not result in a cooler PSU. The key factor is the efficiency of the PSU. Usually around 70% -- this tells how much of the AC power is converted to DC output. 180W drawn from a 70% efficiency PSU means 77W sis lost -- as heat. This would not change if you went to a higher rated PSU unless the efficiency was better (as long as the first PSU is being used within spec).</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR></TD></TR></TABLE><!-- BBCode Quote End --> <br> <br>Ops, I forgot about efficiency. <IMG SRC="modules/phpBB_14/images/smiles/icon_smile.gif"> After re-reading what I originally posted, I'm not sure where I got that train of thought. It didn't really make all that much sense. I must've had too little caffine in my system. <br> <br><!-- BBCode Quote Start --><TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font class="pn-sub">Quote:</font><HR></TD></TR><TR><TD><FONT class="pn-sub"><BLOCKQUOTE>Antec TruePower 430 -- not so quiet. See the comments by HYUM about his TruePower in</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR></TD></TR></TABLE><!-- BBCode Quote End --> <br> <br>Hm, too bad. I guess Antec's definition of "low-noise" doesn't quite match our definition of "low-noise". <br> <br>I've considered buying a TK Power openframe/fanless PSU, but it's too much money to put into this PC now. I'll probably buy one when I start building my HTPC if it'll fit in the desktop case I have picked out. I'm going to try to minimize moving parts in the HTPC. I'll have a .13u P3 (Tualatin?) or a Celeron and try to use the big Zalman flowers and even underclock the CPU (if necessary for stable fanless operation). I'll try to set it up to boot on LAN to remove the HD. I'll have a DVD-ROM drive for playback of DVDs, but that should be the only moving part in it... <br> <br>If the TKPower is really that good, I may get another when I build my next general-use/gaming PC. But, I'll most likely settle for a Zalman PSU. <br> <br>I was going to remove my MB/PSU from my case to cut out the stamped sheet-metal grills from the case. Wtih everything taken out, I figured it was as good excuse as any to buy new hardware, and the local stores carry Antec (convienence factor). <br> <br>I believe air turbulence is the major source of noise in my system now. I've got a 80mm and a 120mm Panaflos running at 5V as case fans, and the PSU fan seems to be noisier than the Panaflos. I can stop the Panaflos and hear almost no difference is overall noise, but when I muffle the PSU fan, the noise level drops considerably. I haven't tried to stop the PSU fans as I'm tentative in sticking anything into a live PSU... <IMG SRC="modules/phpBB_14/images/smiles/icon_eek.gif"> <br> <br>Do the wireframe grilles cause much air turbulence and thus noise? <br>

>>Do the wireframe grilles cause much air turbulence and thus noise? <br> <br>Not at 5-7V, generally speaking. The stamped out grills do, however, and the bad ones also block some airflow; I always cut them out. <br> <br>BTW, while the Zalman has a sleeve bearing fan that is quieter than most, its behavior is not that different from other PSUs like the Enermax or the TruePowers that are thermistor equipped: if the thermistor gets hot enough, then the fan speeds up. In a low airflow but quiet and cool enough system, my Zalman sample started out quiet, but within 10 minutes the fan reached a much higher speed and became quite noisy. In contrast, in Kurt's system, which has much more airflow with 4 case fans (& is likely noisier), the Zalman PSU fan always stays at the minimum level. <br> <br>My TKPower PSU sample is marred by too much coil buzzing noise, and the case (which IS the heatsink) reaches ~50C before settling to equilibrium. I have not actually had it in a case yet, but my early assessment is that it will add a fair amount of heat to the system that MUST be transferred out in some way -- either by direct conduction through the case or some kind of airflow -- ie, fan. My ~GUESS~ is the unit is actually rated for 300W only with forced air cooling of some kind. <br> <br>But lots of people seem to have used it fanless, so until my review work is more complete, this is just conjecture. The <!-- BBCode Start --><A HREF="http://www.siliconacoustics.com/tkinstallation.html" TARGET="_blank">installation pages</A><!-- BBCode End --> at Silicon Audio tells lots. <br> <br>My general observastion after obsessing about PC noise for a couple of years is that no fan means cooling is ALWAYS a challenge & can be expensive to accomplish. A slow quiet fan, however, is sonically about the same as no fan for most applications and is much cooler, less complex & usually cheaper.
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<!-- BBCode Quote Start --><TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font class="pn-sub">Quote:</font><HR></TD></TR><TR><TD><FONT class="pn-sub"><BLOCKQUOTE>Not at 5-7V, generally speaking. The stamped out grills do, however, and the bad ones also block some airflow; I always cut them out.</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR></TD></TR></TABLE><!-- BBCode Quote End --> <br> <br>Thanks. I checked and noticed stamped grill on the case where the PSU is doesn't seem to align perfectly with the stamped grill on the PSU itself. I'm sure that doesn't help. <br> <br><!-- BBCode Quote Start --><TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font class="pn-sub">Quote:</font><HR></TD></TR><TR><TD><FONT class="pn-sub"><BLOCKQUOTE>But lots of people seem to have used it fanless, so until my review work is more complete, this is just conjecture. </BLOCKQUOTE></FONT></TD></TR><TR><TD><HR></TD></TR></TABLE><!-- BBCode Quote End --> <br> <br>I'm looking forward to your review. <br> <br><!-- BBCode Quote Start --><TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font class="pn-sub">Quote:</font><HR></TD></TR><TR><TD><FONT class="pn-sub"><BLOCKQUOTE>My general observastion after obsessing about PC noise for a couple of years is that no fan means cooling is ALWAYS a challenge & can be expensive to accomplish. A slow quiet fan, however, is sonically about the same as no fan for most applications and is much cooler, less complex & usually cheaper.</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR></TD></TR></TABLE><!-- BBCode Quote End --> <br> <br>I'm sure for my general-use PC, I wouldn't mind having a few quiet fans. And, I'm sure it'd be acceptable for the HTPC too, but I'd be more willing to spend the time/effort/money to make it silent. It could be a fun project.
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