This looks like a really promising site. Congratulations!. I enjoyed your review of modding the Enermax, but wanted to ask a question about it. Since the 92mm interior fan is not controlled by the thermistor, why not attach the 80mm fan to the connector that the 92mm fan was connected to? You suggest that it may be undervolted, but perhaps it would be enough to run the 80mm adequately and then you wouldn't have to bother with the thermistor. Alternatively you could just run it outside the PSU and connect it to a line coming off it. That's what I've done in modding others. Again, thank for the great beginning.
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Thanks for your comments. We have high hopes, too, <IMG SRC="modules/phpBB_14/images/smiles/icon_smile.gif"> <br> <br>Your idea is a reasonable one, but if the second fan is undervolted, it is not by much. (I should check that voltage.) So either the stock 80mm fan or the Panaflo 80mm fan would spin pretty close to full speed of the 92mm fan pins. That's too loud IMO. I've run the fan voltage line out to one of the IDE plugs in the past, too, but it's not an elegant solution. With my method, there no extra wiring, the original 2-pin connector is used, and the PSU remains self-contained. <br> <br>I use the thermistor as a manual volume control. I've positioned it so the fan starts at the very minimal voltage & stays there. With the Panaflo, it's essentially inaudible. <br> <br>Which PSUs have you modded?
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I started with an older PC Power and Cooling 235W Economy PSU and stuck in a Panaflo L1A running at full voltage (off one of the PSU lines). It's quiet compared both to the Zalman and PC Power and Cooling 275W Silencer, and is really enough power for the system I'm running (1Ghz P3) . The Zalman has the same problem that you identify with the Enermax--it starts out nice and quiet but quickly ramps up. I've also done the earlier Enermax (non-FC) (I'm waiting for a mesh filter to cover the 92mm opening) and had done the same routine as the PCP&C, but am now thinking of redoing it with one of the internal connectors.
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Mike, another question--why do you think the voltage on the 92mm fan is greater than the 80mm fan, so that it would spin faster at full voltage than on the 80mm pin?
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Whatever the voltage is on the 92mm fan, it does not change. I think they do this to ensure some airflow into the PSU no matter what the 80mm fan is doing. So on the one hand, they can advertise thermally controlled fan speed (which suggests lower noise & machine intelligence) but with the second fan going all the time, even if the first fan is hardly going, they assure a certain airflow into the PSU. I think it's an inexpensive failsafe with marketing panache -- fans at the OEM level are dirt cheap. <br> <br>I see this cleverly continued in the Enermax Whisper EG365P-VE I am examining now. Same fan models, BTW. Here the 80mm fan speed can be varied from 1500 to 3000 rpm with a nice action rotary control on the back. At 1500 rpm, you know that fan will be pretty quiet. And they say the 92mm fan is now thermistor controlled. BUT the 92mm fan speed never appears to change. Why? Because the thermistor is not glued to the top of the coil. No, this one is glued to the <!-- BBCode Start --><I>center</I><!-- BBCode End --> of the coil. I can only see one reason for this: to make sure the 92mm fan never slows down. So why put the thermistor in the circuit? Well, thermistors are cheap. That thermistor lets them say: manual variable control for the 80mm fan, thermal control for the 92mm fan. Wow! How enlightened and sophisticated, it must be really advanced and quiet. <br> <br>They still are guaranteed the airflow of the 92mm, which incidentally guarantees a certain minimal noise. <br> <br>Perhaps I've given too much away from the coming review. <br> <br>You think I am too cynical?
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I bought the enermax and panaflo fans for my latest and greatest box, but I haven't been happy with the noise level. <br> <br>I would, however, be concerned about the use of only one fan, especially the panaflo, in the Enermax mod. My experience is that the Panaflo is quieter, but will it move enough air by itself to keep the ps cool enough? Will the ps survive?
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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>I bought the enermax and panaflo fans for my latest and greatest box, but I haven't been happy with the noise level. <br> <br>I would, however, be concerned about the use of only one fan, especially the panaflo, in the Enermax mod. My experience is that the Panaflo is quieter, but will it move enough air by itself to keep the ps cool enough? Will the ps survive?</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR></TD></TR></TABLE><!-- BBCode Quote End --> <br> <br>Heat has not been an issue at all. The air blown out by the Panaflo is only warm, never hot. At a later date, I may try thermistors readings at the heatsinks before/after mods. There's a very low likelihood of any real *danger*, as PCBs and electronic components pretty fire-retardant. There are some people, like Cub Lea, who have run their generic PSU fanless for years & never run into any problem. His pages used to be here but the link appears broken: <!-- BBCode Start --><A HREF="http://"http://www.cublea.com/rants/shutup/index.html" target=nw" TARGET="_blank">Shut that thing up!</A><!-- BBCode End --> I admit I have made one Enermax fail, but that one was subject to a lot more serious abuse & torture, like many major shorts across all its voltage lines over a period of 2 years.
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Also, Mike has recently posted an article addressing this very question "will the psu survive with only a panaflo @5v". The temps rise, but not enough for concern. I have run my higher wattage 430W model with the same mod inside my case now for what...2 months with no problems whatsoever. If I didn't do it myself, I wouldn't even know the difference, except that its now virtually inaudible;). I think for psu's this is the best way to go, not fanless. I mean, the temps are like 25c cooler with just a very very slow spinning panaflo fan that makes BARELY any noise. Any harddrive noise you have (and you will, unless you use solid state) will easily drown out a panaflo @5v. Better yet, do Mikes resistor mod and run it at 3.5-4v! Ooooo that reminds me I've been meaning to try this and still haven't done so...wish I could find those resistors I bought at the ratshack last time...doh! <br> <br>-Ken
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Wow; I thought I was going nuts, or had gotten some sort of fake or bad Enermax, because my 350W Enermax Whisper didn't seem to be much quieter than the power supply I had before. Thanks for the article; I'm going to have to try that. <br> <br>Is it possible to just remove the 80mm fan, leaving the 92mm fan in? If the airflow isn't that important, can it just be maintained by the 92mm?
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Oops; nevermind; I just looked at the way it's set up; the airflow patterns would be completely different because you'd end up with positive pressure in the PSU, and there wouldn't be much flow out of the case.
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Actually, the 92mm alone would probably work fine, would would help cool the CPU a bit better, but you would want to remove the 80mm fan altogether & block all the other vent holes in the PSU (except for the 80mm hole). But use something to put the wire grill back on over the 80mm hole for safety...
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I was wondering how this would apply to the Enermax Whisper FCA PSU's that come with a built-in pot. According to your previous post, this apparently controls the 80mm fan that was the problem eliminated by moving the thermistor away from the coil in the article. But I have this PSU, and it seems to suffer from the same problem, getting louder as time goes on. So I'm assuming this is the 92mm fan speeding up in response to the heat. So if I eliminated this fan altogether, I'd have pot. control of the one remaining 80mm fan, right? And then if I wanted to I could replace the 80mm fan with a Panaflo, and have basically the same solution as you added at the end of the article, no? <br> <br>-tslugmo
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tslugmo: <br> <br>I am afraid the answer is no. <br> <br>If you remove the 92mm fan, the min speed of the 80mm fan will go up because the thermistor gets hotter. You'll find that if you set the pot for max 80mm fan speed, the inner fan will not speed up over time because the thermistor won't get as hot. The pot is NOT independent of the thermistor which controls the 92mm fan. It appears to be in the same control circuit, but AFTER the thermistor. You need to replace the thermistor with a 100k-ohm resistor (or just try snipping the thermistor off, which is infinite resistance -- it might have the same effect) or move it to a cooler spot to maintain the 5-12V range of the pot without the 92mm fan. <br> <br>I will cover this in more detail in a review of the EG365P-VE that's coming soon.
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>>tslugmo: <br>>> <br>>>I am afraid the answer is no. <br>>> <br>>>If you remove the 92mm fan, the min speed of the 80mm fan will go up because the thermistor gets hotter. You'll find that if you set the pot for max 80mm fan speed, the inner fan will not speed up over time because the thermistor won't get as hot. The pot is NOT independent of the thermistor which controls the 92mm fan. It appears to be in the same control circuit, but AFTER the thermistor. You need to replace the thermistor with a 100k-ohm resistor (or just try snipping the thermistor off, which is infinite resistance -- it might have the same effect) or move it to a cooler spot to maintain the 5-12V range of the pot without the 92mm fan. <br>>> <br>>>I will cover this in more detail in a review of the EG365P-VE that's coming soon. <br> <br>Aha. Sorry, I r teh noob, and very inexperienced with electrical bungling. So you mean to say that the control I have with the knob on the PSU only controls the speed within the relative range that the thermistor sets the 80mm fan at, dependent upon temp.? However, if I didn't modify the thermistor by adding a 100k-ohm resistor, lopping it off, or moving it further away from the coil, the 80mm alone (at its new higher speed) should still be quieter than the 80mm + the 92mm, no? Plus, if I replace the fan with a Panaflo, this should cancel out any added noise effect by the rise in speed, don't you think? I see what you're saying, though, that in order to maintain the range of 5v-12v, I'd have to modify the thermistor. <br> <br>Thanks millions for your help, Mike. And your unending patience. Your devotion to this site and its users is clear, your attention to detail is impressive, and I expect it to result in a site with quite a bit of potential. Informing the pros without intimidating the newbies is quite an accomplishment; You seem to be pulling it off with ease. Keep up the good work! Can't wait for that new review... <br> <br>-tslugmo <br> <br>

I've now modded both my Enermaxes by removing the 92mm fans and covering the opening with aluminum mesh filters, replacing the 80mm fans with Panaflo L1A's, running them out of the PSU and connecting them to one of the lines. Both run very quietly, and, interestingly, my mobo temperatures seem a little bit lower. I speculate that the internal fan just creates a less smooth airflow and doesn't aid in cooling. The air coming out of the PSU doesn't even seem warm.
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Here is the functional link to the Cub Lea page mentioned above: <!-- BBCode auto-link start --><a href="http://www.cublea.com/rants/shutup/index.html" target="_blank">http://www.cublea.com/rants/shutup/index.html</a><!-- BBCode auto-link end --> ... looks pretty scary to me (esp. the PSU-without-a-case-thingy). <br>BTW, really looks like a promising site - I came here via a link from 7volts.com.
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The mod works great for me until me case temp gets up to 27C (which is pretty unavoidable right now as it's summer here) I moved the temp diode outside the PSU through the openings in the back but still no luck <IMG SRC="modules/phpBB_14/images/smiles/icon_cry.gif"> <br> <br>I'm thinking of replacing the fan with a Papst - either a 12db/20 CFM or a 19db/26 CFM. My main concern is the fan header in the PSU.. How exactly did you modify the fan header do be able to connect the replacement fan ?? <br> <br>Oh and one other thing - looks like you're not the first to have done this. <br><!-- BBCode Start --><A HREF="http://members.shaw.ca/mikechinvan/quiet_at_2G_3.htm" TARGET="_blank">- Article from feb. 2002</A><!-- BBCode End -->

Funny you should mention the other article -- I guess you didn't look too closely at the author's name, huh? It is the original P4 article I wrote & posted to a free web hosting provided by my ISP... <IMG SRC="modules/phpBB_14/images/smiles/icon_smile.gif"> <br> <br>Which Enermax do you have? Sounds like one without the manual speed knob? <br> <br>If you know how to solder, replace the thermistor with a 100K potentiometer. See the <!-- BBCode Start --><A HREF="http://www.silentpcreview.com/modules.php?op=modload&name=Sections&file=index&req=viewarticle&artid=9&page=5" TARGET="_blank">postscript</A><!-- BBCode End --> at the end of the "Quieting the Enermax & other thermistor fan PSUs" article for full details. You can just run a long wire and let the potentiometer dangle outside the case or drill a mounting hole on the back of the PSU. Clean up ALL metal bits very carefully after drilling! I hope I don't have to tell you about unplugging from AC, and avoiding other dangers... <br> <br>Now you can set the fan to whatever speed you want -- minimum if low noise is the goal; higher if you think the PSU/CPU/PC is getting too hot.
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hey mike, thanks for the great new site! <br> <br>i'd like to say, i really enjoyed your enermax PS article. i recently got an antec "true power" supply and ran some equivalent investigations on it after reading your article. i'd like to share some of my results. basically, it confirms all things you said about the enermax. <br> <br>first on the PS features. the PS has a couple nice features. it has +/- 3 % regulation on the major rails, and it uses remote voltage sensing at the connector to help achieve this. it also has temperature controller fans as well as a dedicated 4-pin molex power connector just for case fans connected to the same temperature control for the internal fans. both internal fans temperature controlled. <br> <br>temperature control is by lowering the DC voltage. i measured the voltage at cold startup and the voltage supplied by the temperature controlled fan power connector starts between 5.5V to 6V. this is a bit low as most fans including panaflo (and i think papst too) are spec'd to start at 7V. however, i found that my 120mm L1A panaflo's started at the low voltage (everytime so far fingers crossed) as well as my 120mm NGL papst. however, i have a small 80mm PCP&C silnecer fan that would not start up under 6V, but would just over 6V. if you use this feature on this PS, watch out for this. <br> <br>I replaced my 80mm fan with the silencer fan and i run it at 12V instead of the temp controlled voltage. i ran the PS outside of the box and ran prime95. i have a athlon XP 1800+. i found the hotest spot on the heatsinks and attacked a temp probe from my fluke meter. i attached it to the heatsink because frankly i don't want to reach too far down into the PS and shock myself. with the cover off fans off, my meter read over 60 degree C after maybe 10 minutes. i put the cover back on with the fan running, and it fell down to aroud 35 degree C! pretty much the same result you posted in your article, mike. int his test, the 92mm fan was disabled beacuse I figureed at that low temp, the second fan isn't needed. i may rerun the test with the intake fan on at 12V, at 7V, in and out of the case, if i feel up to it, just to satisfy curiosity. but i have no practical need to run the tests. <br> <br>if someone wants me to really runs these tests, let me know, as it might motivate my more. if no one cares, i probably won't feel motivated to pull my PS out of my box again. <br> <br>my PS setup back in my box is now the 80mm silencer at 12V as exhaust, the 92mm intake fan removed and the hole taped up. all intake air should be coming from the front vents so that is passes over both heatsinks. i taped it because the 92mm fan is removed and with that big gaping fan hole is there, most of the intake airflow would move from that hole to the exhaust, and the heatsink by the front intake grates would probably get very little airflow over it. practically speaking, i don't think the taping was that necessary, though. <br> <br>some thoughts for discussion: for the PS, i think the second fan for intake is unecessary for the PS alone. the second fan is recommend by amd to cool the CPU to be a "recommended amd approved PS". for the PS, i find that the 92mm fan does little to improve the PS cooling itself. in fact, because of the _potential_ positive pressure pushing some of the warm air back into the case through the front grates (but away from the CPU) instead of exhausting all the air outside the system, it may actually increase the PS temps. i don't have empirical proof for this, just a guess based on the inforatmion i have collected so far, which is far from complete evidence. it may help cool the CPU, but may or may not help keep the PS cooler. if your CPU is cool enough to begin with, i would consider either not getting a two fan supply, or removing the intake fan if you don't need it.
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Welcome hyum, glad you enjoy the site. <br> <br>>> it has +/- 3 % regulation on the major rails, and it uses remote voltage sensing at the connector to help achieve this. it also has temperature controller fans as well as a dedicated 4-pin molex power connector just for case fans connected to the same temperature control for the internal fans. both internal fans temperature controlled. <br> <br>Sound like useful features. <br> <br>>>temperature control is by lowering the DC voltage. i measured the voltage at cold startup and the voltage supplied by the temperature controlled fan power connector starts between 5.5V to 6V. this is a bit low as most fans including panaflo (and i think papst too) are spec'd to start at 7V. however, i found that my 120mm L1A panaflo's started at the low voltage (everytime so far fingers crossed) as well as my 120mm NGL papst. however, i have a small 80mm PCP&C silnecer fan that would not start up under 6V, but would just over 6V. if you use this feature on this PS, watch out for this. <br> <br>There's no 12V I've tried personally that does not start at consistently 5V. Not unless bearings are shot. So your fan is unsual -- or maybe the bearing needs some lube? <br> <br>>>I replaced my 80mm fan with the silencer fan and i run it at 12V instead of the temp controlled voltage. i ran the PS outside of the box and ran prime95. i have a athlon XP 1800+. i found the hotest spot on the heatsinks and attacked a temp probe from my fluke meter. i attached it to the heatsink because frankly i don't want to reach too far down into the PS and shock myself. with the cover off fans off, my meter read over 60 degree C after maybe 10 minutes. i put the cover back on with the fan running, and it fell down to aroud 35 degree C! pretty much the same result you posted in your article, mike. <br> <br>Running this PCP&C fan at 12V is quieter than the stock fan at 6V? Really? Or does the internal PSU fan voltage climb quickly like the Enermax? I gather this mean the stock Antec "true power" PSU is NOT very quiet? It would be nice to get details of the stock behavior of the PSU. <br> <br>>>my PS setup back in my box is now the 80mm silencer at 12V as exhaust, the 92mm intake fan removed and the hole taped up. all intake air should be coming from the front vents so that is passes over both heatsinks... i don't think the taping was that necessary, though. <br> <br>Taping up one or the other of the holes DOES improve overall airflow through the PSU, providing more of a chimney effect. <br> <br>>>some thoughts for discussion: for the PS, i think the second fan for intake is unecessary for the PS alone. the second fan is recommend by amd to cool the CPU to be a "recommended amd approved PS". for the PS, i find that the 92mm fan does little to improve the PS cooling itself. in fact, because of the _potential_ positive pressure pushing some of the warm air back into the case through the front grates (but away from the CPU) instead of exhausting all the air outside the system, it may actually increase the PS temps. <br> <br>The experiment to try is to leave the 92mm hole open & tape up the front vents. In theory, this SHOULD provide more hot air removal from around the CPU & thus improve temps a bit.
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>>There's no 12V I've tried personally that does not start at consistently 5V. Not unless bearings are shot. So your fan is unsual -- or maybe the bearing needs some lube? <br> <br>it's a brand new PCP&C silencer fan so i doubt it needs lubrication. maybe unusual or maybe this type of fan needs more startup torque than the panaflo's or papst. don't know. if you move it with your finger, it spins, so it's only a startup torque issue. since it below starting at below 7V which is under spec, it's not defective. could also be a "yield" issue where the same fan in a different lot will work over spec better. again, i dont' have enough samples to make a statisical observation. 7V is the guaranteed spec. the usually get these types of specs from statisical yield analysis. so some small percentage is going to fail probably under 7V. i may have just got an "unlucky" one, or maybe the startup torque on this particular fan is high by design. <br> <br>>>Running this PCP&C fan at 12V is quieter than the stock fan at 6V? Really? Or does the internal PSU fan voltage climb quickly like the Enermax? I gather this mean the stock Antec "true power" PSU is NOT very quiet? It would be nice to get details of the stock behavior of the PSU. <br> <br>well, i was planning to run the silencer at temp control which would have been quieter than stock, but that didn't work. by the way, i forgot to mention, i replaced the stock fans with the 80mm silencer and the 92mm with a papst NGL both on temp control from the PS and when the 80mm didn't startup by itself, i touched it with my finger to get it going. both these fans probably spun slower than the stock fans. anyway, the PS got VERY hot this configuration (such that that case around the PS was noticably warm). i got rid of the 92mm fan and decieded to connect the silencer at 12V. it's very quiet, but not silent. i don't know if it's quieter than the stock fan at 6V though, because i never ran the stock fan without the 92mm fan. i also didn't want to go through a whole matrix of testing. the silencer w/o the 92mm fan is quiet enough that the loudest components in my system now is the HDD vibration. i'm working on that next. until then, i may not change my PS fan again as i am happy with the noise now,... that is unless i'm curious and just want to run through more testing matrixes for knowledge sake but for now this works for me <IMG SRC="modules/phpBB_14/images/smiles/icon_smile.gif"> <br> <br>>>>>my PS setup back in my box is now the 80mm silencer at 12V as exhaust, the 92mm intake fan removed and the hole taped up. all intake air should be coming from the front vents so that is passes over both heatsinks... i don't think the taping was that necessary, though. <br> <br>>>Taping up one or the other of the holes DOES improve overall airflow through the PSU, providing more of a chimney effect. <br> <br>while i agree in theory, leaving one hole taped _should_ be better which is why i tried it both way. in my case where the PS was out of the case and the the lower hole untaped and taped, the difference was minimal such that is barely measured any different within margin of error. meaning, in the setup i tested, the empirical difference was negligable. however, for other systems and test setups, i'm sure it could produce different results, so it's worth trying. i'd definately recommend trying it both ways for other people and seeing what they get. <br> <br>>>The experiment to try is to leave the 92mm hole open & tape up the front vents. In theory, this SHOULD provide more hot air removal from around the CPU & thus improve temps a bit. <br> <br>i may try this out. the only thing i'm worried about is that while it may remove more hot air from the CPU, the front heatink by the front vent may get stagnating air as the air will flow form the bottom hole to the exhaust. this may cause the front components to get too hot. <br> <br>because it's simple and i can do it without removing the PS from the case, i may try it anyway. i'm curious, and it doesn't require too much additional work <IMG SRC="modules/phpBB_14/images/smiles/icon_smile.gif"> i'll let you know what results i find.
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