Weird coil whine when using 4pin CPU fan

[slim01]

Hi guys, but of a weird one.

I recently bought a corsair RM650x in the hopes it would get rid of coil whine which was driving me CRAZY for ages... NOPE.

After unplugging *everything*, and using my old psu, now a meter away from case - still a whine... From cpu area???

So I unplugged the (4pin) cpu cooler and plugged into PWR_FAN(3pin).
HURRAH! No loud whine...
But is loud at max rpm... So now I've plugged into the SYS_FAN2 (4pin)...

Currently set us as below, any suggestions appreciated;

Spoiler

Is it ok to use SYS_FAN2 as cpu fan?? Will this gradually rise the RPM with CPU temps or is SYS_FAN2 getting its temps from somewhere else?
60mins of prime = Not going past 60oC
HW monitor shows a fan (not sure if CPU or not) gradually rising from 990 - 1600rpm.


Should my (3pin) fan - now in CPU-FAN, change rpm depending on CPU temp or is that the whole point of a 4th pin - PWM??


Thanks guys

 

[slim01]

no-one? Arg......

 

[slim01]

its probably the pwm/switching voltage on and off that's causing the noise

did you try turning off c1e in the bios? see if that stops the noise when connected to 4pin header

try setting fans to voltage control in bios,might let you lower the speed

no havent tried C1E... Will try and find that soon.

Might be handy I am planning to overclock my CPU for fallout 4.

Also another quick question - I just bought an extra 8gb (2x4gb) of memory, rated at 1866mhz, 9-10-9-27 but when I try and run it at those speeds PC does not even POST.
If the memory is rated to run at those speeds how come I can't? MUST I overclock cpu in able to get memory speeds up?
I know the 250mhz won't make much difference, but will be handy to know for when overclocking cpu, as I can;t keep it constantly overclocked (pc does not idle when overclocked so just want to turn it on when gaming on fallout 3 or something).

Thanks