Windows 7: Power Supply Question

I just got a new 500 watt power supply. The old one was overheating. The new one has a switch for a normal fan or turbo fan. The temperature runs around 48 C most of the time but has spikes up to 70 C (I have a temperature monitor software). When I put it on Turbo the system stays nice and cool all of the time. Is it going to hurt anything to leave it on Turbo all of the time? Thanks,

It will hurt nothing but your power bill (how ironic), and your ego if you are competing with someone for the quietest machine.

Of course, it may decrease the time before the fan bearings wear out, but I don't think that's a big concern at all.

Thanks very much.

Do you have a rear case fan fitted? If not, fit one (if you have space). Use the largest your case will accomodate. This will help in drawing warm/hot air out of the system before it reaches your PSU, which will help it run cooler and quieter (since you won't need to use the turbo mode). If your temperature monitoring is for the PSU, I would be concerned at temperatures of that level - is the PSU providing sufficient wattage (amperage) on each voltage line? If your old unit overheated, this could possibly indicate that your system was trying to draw more power from it than it could supply, with the result that its internal components were being overheated. You state that the new PSU is a 500W model. What was the rating of the old one? I might have gone for a 600-650W model instead as that would have more power reserve.