Several weeks ago, I spec'd a system here with your help. The build went smoothly (I went slow) and I'm pleased with the result. The one thing that annoys me is the power supply. I bought an Antec NeoHE 550W because it's supposed to be quiet and use less power. It does, but the PSU fan keeps cycling up and down when I'm running normal applications (IE, Word). I believe -- correct me if I'm wrong -- that this is because the system is drawing very little power. (I have a Core2Duo E6600, not overclocked, and a Gigabyte Nvidia 7600GS with no fan and no separate PSU connection.) So, the PSU thinks it can turn its fan off or down. But then it decides, "Just a little." Again and again... When I'm running a more demanding application (= Flight Simulator), everything settles down.If my analysis is correct, what I need is some background application that will kick up my CPU usage and force the PSU to draw a little more power. I don't listen to music while I work, or I could use WMP for this. Any ideas? I can only defrag my disk so many times a day...

Try http://sp2004.fre3.com/beta/beta2.htm, or if you want to do something more constructive try either setiathome.ssl.berkeley.edu or folding.stanford.edu. Gary

This will tax it:http://www.mersenne.org/prime.htmJimhttp://www.hifisim.com/Active Sky V6 Development Team Active Sky V6 Proud SupporterHiFi Beta TeamRadar Contact Supporter: http://www.jdtllc.com/AirSource Member: http://www.air-source.us/FSEconomy Member:http://www.fseconomy.com/

That PS uses a thermal probe on the heat sink to control the fan speed. Pushing up the PC load to keep the fan at one speed sure seems like a kludgy way to control your fan speed.I'd send a note to Antec for their suggestions. Also, forced airflow from another fan on the other end of the PS might keep the sinks cool enough in low-load operations to keep the fan from cycling.But...that said, if your PS fan is cycling like that under a low CPU/GPU load, it may be telling you something important about the airflow through your case...RegardsBob ScottATP IMEL Gulfstream II-III-IV-VSantiago de Chile

Thanks, Bob. I've sent Antec a description of the problem.

Here's an update. I took the cover off my case to watch what was happening and it turns out that the fan I could hear cycling on and off was my CPU fan! (Stock Conroe.) Intel has some logic to moderate this, which I was able to activate on my motherboard, but using this the fan speed was much higher (= louder) than was needed for cooling the CPU. Instead I've been using the EasyTune software that came with my Gigabyte motherboard to set a higher minimum fan speed. Result: much less oscillation and noise.

Thanks for the update and glad you got it sorted without having to resort to artificial power consumption!Gary