Power supply problem?

[Dan The IT Man]

Hi there,

I have currently purchased a new PSU: Corsair Builder Series CXM 750W Modular 80 PLUS Bronze Certified ATX/EPS PSU The PSU seems perfectly normal when the system is either idle or browsing the internet. However, when the system becomes under load for example when I run a game, the PSU makes a "buzzing" sound, almost constantly until the game is closed. I have tried multiply cables (that came with the new PSU) and tried them in both of the 8 pin rails but still the problem persists. I have also tried loading a game without the GPU in and have had the game(s) running from the onboard graphics. This still made the "buzzing" sound but very very silently compared to when my GPU was plugged in. (Writing this now and no buzzing).

I have tried contacting Corsair but they seem reluctant to reply. Is this a PSU problem or just an unlucky combination of my hardware? Or perhaps something else?

All assistance is greatly appreciated and put my thoughts at rest.
Thank you in advance.

My Current system is:

CPU: Intel i5 2500k @ 3.3GHz (Not OC)
Mobo: Asus P8 z77-LX (NEW)
GPU: Geforce GTX 780Ti 3GB (NEW Not OC)
RAM: Kingston 8GB (2x 4GB) @ 1333MHz
PSU: Corsair 750W Semi Modular
Storage: 240GB Intel SSD 6GB/sec / WD 2TB 6GB/sec / WD 500GB 3GB/sec

Cooling: 5x Corsair Air Series 140mm, x1 Antec 140mm
Case: Fractal Design Midi

 

[Dark Lord of Tech]

For gaming builds you are better off using a higher end power supply.