I bought the Q-Tech PSU about 20 days ago. The first few days I thought it was amazing. I couldn't notice it. <BR>It is about 5-6 days now that that the PSU is more loud than it was earlier. I don't know if I have become very demanding, but I am absolutely sure that it is not as silent as it used to be and it has become quite hot as well. <BR> <BR>I know that now in the summer it is logical for temperatures to rise,but that can not justify the fact that the PSU is louder straight from boot-up. The fan certainly runs much faster than in the first days when I bought it. It could be something similar to what happens on the Enermax PSUs. The heat sensor of the Q-Tech PSU might be placed somewhere that gets very hot easily and therefore causing the revs of the fan to go up. <BR>Neverhteless, I don't want to open it yet to check if that is the cause because I wouldn't want to lose the warranty. <BR> <BR>I had modified my previous PSU but my new Q-Tech was better. I will put them again to the test now, to see if there is still a difference. But before someone buys this product I would recommend that they wait until it is put to the test with the ZALMAN PSU or any other.
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Intesresting observation. <br> <br>Which model is it? Apparently, even among units with the same power rating, there is more than one model -- the part # is different. <br> <br>I have a QT-02300, a 300W unit, powering an AMD XP system that is not in a case, just sitting on a test bench. The fan does not seem to have gone beyond the start up speed. No voltage monitoring of the fan set up yet, so it could be rising slightly without my being aware of it. Putting it in a case will increase its temperature by 5-10C so well see what happens when I do that. <br> <br>BTW, the Zalman doesn't stay at startup noise level all the time either; it does speed up under load or when the system is left on for a long time on a hot day. It speeds the fan up a bit faster (sooner) than the Seasonic does. <br>

The Model No is: ATX-1125BTA QT . At least that is what is written on the PSU. It is a 300W model. I can't find a part No anywhere. <br>It powers an Athlon XP 1700 <br>

It's not the same as the review sample I have. If you have a digicam, take some pics & email them to me & maybe we'll be able to tell whether they just changed the label. This one has a proper wire grill & active PFC (doesn't have 110/220 switch).
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Here's the explaination: <br> <br>The 1125 BTA QT reacts diferent on power consumption then the QT2300. The 1125 BTA QT reacts a bit more 'extreme' to higher power consumption then the QT2300. <br>So you can say the noiselevel margen between low and high power consumption is smaller with the QT2300 then with the 1125 BTA QT. <br> <br>I hope this explains the issue... <br> <br>Michael van der Jagt <br>Qtechnology <br><!-- BBCode Start --><A HREF="http://www.silentpc.nl" TARGET="_blank">Make your PC Silent!</A><!-- BBCode End -->
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There are a number of power supplies out there that simply carry a different name but are actually identical to another unit.

Q-tech sells Enhance power supplies. Model name change from ENP-0730 to QT-02300 is one such example of two identical PSUs. Find 'em cheap at a website like http://www.newegg.com Save around 40%.

Any questions? You can email me at kooltronic2002@yahoo.com

Kooltronic2002.

Interesting, I looked at that ENHANCE ENP-0730 at www.newegg.com, and the customer reviews are not too great. One of them compares the sound of the PSU to his diesel truck.

kooltronic2002,

I had a look at the pics at both the Enhance web site and new egg, and I have to say none of the PSUs there LOOK anything like my QT-02300 review sample. Not saying it isn't so, just that they don't look alike at all. The cover vent holes are completely different, as are the vent holes on the back, and my sample has a wire fan grill while the ones pictured on the above sites have cutout grills.

I have to admit that other Q-tech units actually have exactly the same model #s - 1125B, 1125BTA.

What makes you so sure Enhance makes the Q-tech QT-02300?

Hi kooltronic & Mike:

Hop I could help on this issue, I had tested more than 10 high quality brand, and Enhance was one of the high quality one.

I try to check the web site www.enhance.com.tw and find
1. ATX 2.03
ATX-1123B ~ ATX-1123-QT
ATX-1125BT ~ ATX-1125-QT
2. ATX 12V
ATX-1125BTA ~ ATX-1125BTA R300
3. ATX 12V (power factor correction)
ENH-0130 ~ QT-02300
ENS-0240 ~ ENS-0240-QT
ENS-0246 ~ ENS-0246-QT

The specification of QT-023000 was same with ENH-0130 not ENP-0730
Also you could find high end ENS-0240 and 0246 was totally the same

Another simple way to find more similar OEM model, you could get www.google.com and type the model number like ATX-1125BTA for search, then you will find more

It was a easy way to add a OEM logo by mutliple list, you could either pay less for keep the same model name or pay more for specific model name (like QT-02300)

Some of the PSU manufacturer will provide the option of I/O switch, AC outlet (for old Monitor), or wire fan grill to make little difference

I will try to find more information regarding to the OEM silent PSU

I confirm what Redis said, I've bought a QT 02300 one month ago and if it boots quietly, it becomes very loudy after a while. It's so loudy that I've uninstalled it and reinstalled my old OEM PSU.

Wow, that's a surprise & a bummer for you! It's not what I saw with my review sample, which did exhibit a small amount of coil whine from titme to time, but not fan speed-up. Note that Regis has a different model which does have a noisier fan. What are the details of the system you're running?

It's a PIII-1GHz, 512 MB RAM, HD 40 GB, CD-R and CD-RW.
It has been a surprise for me too. I was expecting better results. Maybe the power supply is ?defective? (don't know how to say it in english) or my old PSU is really quiet.

err, having read these comments I'm no longer sure I want a Q-Tech...

I just recieved my QT 02300 Today, and it is QUIET-i have to put my ear right up to the fan to be able to hear it. However, i must warn that it seems to run much warmer than the stock psu that my case came with (which had a very noisy fan). As such, my case and cpu temps have both warmed up about 5c. So, it seams that the q-tech is the quietest of the psu's reviewed, but also the warmest. for me i dont think it will be a problem, but i wonder about during the summer months.

System specs:
Full tower case
athlon xp 1600 with Volcano 9 hsf (1300rpm fan)
3 Zalman quiet case fans.
3 LOUD ibm and WD hdds (next on my list to quiet down)

afaik there are two versions (maybe more) of the 300w from Qtec

a cheap version (with no wire grill and no thermistor for fan speed)

Higher price version which quietpc.com provide today (with wire grill, only air intake's are opposite the fan that looks like a load of drilled holes, and there is a thermistor on the biggest heatsink).
These are not my pics

Also notice the heatsink on the right of the picture


now look at the SPCR model


this is a pic from a review of another site, same 300w Qtec psu different heatsinks

I believe that the PSU that was reviewed on SPCR was only equiped for the PSU in mind, to get the quality certificates the 'newer' Qtec psu's must have had to comply with some ATX standards which means it has to help with removing hot air from the case aswell as cooling itself. OR to keep a sustained optimal efficency from the psu, they found it better if the psu operated cooler than previous models.

When I boot my pc after the PSU's heatsinks have had time to cool down, the fan is very quiet, but after playing a game the fan quickly speeds up, the majority of the noise is comming from the air hitting the 'drilled holes' air intake.

Since some ppl have ran this PSU with no fan, you could mod the psu the same as the enermax, move the black thermistor away from the heatsink (its not glued or nothing).
**WARNING** the heatsinks where LIVE on my psu, if your gonna move the thermistor, remove the power cord and psu from case and leave it for about an hour.

Interesting... thank you for this little tidbit!

I heard a bit about this before, that the newer Q-tec PSU's were supposed to be a bit more noisy.