Hi Dave and WELCOME TO SPCR!!
Thanks for your welcome and for your helpful reply!
They don't fit bigger heatsinks, but I cannot say 99% sure for the fan controller. It has to be ordered from Fortron if they want a different fan controller, atleast I really doubt Nexus would do this kind of an operation themselves.
I wrongly assumed, in my original post, that the big orange fan in Nexus PSUs is a Nexus fan. On checking the review here I found that it's a Yate Loon D12SM-12, which appears to be specified as 1650 RPM @ 12V, 70.5 CFM, 33dB, whereas the Nexus is 1000 RPM @ 12V, 36.87CFM, 22.8 dBA. So I was wrong to use the Nexus PSUs as an argument for the advisability of putting a Nexus or other low-speed fan in the FSP.
The S12 does have better efficiency than your Fortron
Not by much though, if the figures in the following review can be compared with those from the SPCR review of the S12:http://www.xbitlabs.com/articles/other/display/fsp-psu_9.html
It seems that the ATX v2 FSPs are a good bit more efficient than the older models.
and it also has a better fan controller.
Yes I get that impression, though this is another area where the ATX v2 FSPs seem to have improved according to the Xbit review - see the fan speed vs output load graph there. This shows the speed staying at minimum to about 150W load, though I imagine that will depend heavily on the test rig and ambient temperature. My system (details in sig) shouldn't draw anywhere near that.
I don't notice the PSU fan ramping up in speed; it's always about the same level, the problem is that that level is a bit louder than I'd like. To give you an idea, when the house is quiet I can walk the 2 metres from my PC to the door, then 2 metres down the hallway (all carpeted) and still just hear the PC (with the door open).
I haven't yet opened up the FSP to see what fan it has; it's ball bearing, but I believe FSP use both Yate Loon and Protechnic.
As a starting point the S12 is better than the Fortron. (noise wise, considering build quality I would say Fortron. But this is a matter of taste / butt-feeling
) If you're irritated down the road by the PSU noise you can then start to consider about PSU modding.
I found a thread on fan-swapping the S12, AFAIR the conclusion was that the S12 had been wrongly identified as the noise culprit and that the swap would only ever be worthwhile if connecting the fan to an external controller.
Depending on your system's power levels, at low power levels a fan swapped Fortron might even be better than the Nexus. But I would say you don't really have stress the Fortron a lot to make the fan speed up.
Did you mean Nexus or Seasonic?
I'm at low power levels; as I said, the problem is the base noise level rather than ramping up under load. The fan just seems to run faster, or at least more noisily, than I was hoping, right from a cold start. Of course I may hit the speeding up problem too in warmer weather. I can cope with the machine getting a little bit noisier when doing some serious compiling or encoding (when I can disappear for a cup of tea
), so long as it returns to quietness when it's done.
So I say S12. Should work OK and it gives you a better starting point for PSU modding in the future.
Thanks for your detailed and reasoned response! I'm still mulling it over, as the strongest arguments in favour of the S12 (staying quiet to higher power) aren't particularly applicable to my situation (lowish-power PC, tolerance for a little more noise under load).
I suppose though that in order to get significantly lower noise from the FSP, I will need to reduce airflow, either via a resistor or a lower-speed fan. (Any opinions on whether there's much scope for lower noise with similar CFM by fitting a better fan? Difficult to say, I suppose, as we don't know what fan I have!) In which case the PSU is getting less cooling than it was designed for, which worries me a little. Whereas the S12 is designed to operate with its (I assume) lower airflow, so I'd expect better reliability and longer service life. Other things being equal, which they never are.
I seem to be talking myself towards the S12, even in my low-power scenario. I'm still very much open to having the benefits of others experience and expertise, however.