Hey. I just wanted some people's opinions on something. It's rather complicated. I recently built a mini-ITX PC to use as a LAN rig, but I've had some rather annoying issues. Spec; i5 4440 @ 3.3 GHz 8GB Corsair 1333MHz MSI H87i Sapphire AMD Radeon R9 270X Dual-X The first case I used was a Silverstone Sugo SG05, with a Silverstone 450W 80 Plus Bronze SFX powersupply. After a while, the power supply started to develop (it wasn't instant) a really loud buzzing noise, not the usual whining associated with coils, but an electric buzzing noise, at both idle and under load from the GPU. Similar to a cable tie caught in a high-speed fan. Wasn't exactly that, or any fan-related or vibration issues for several reasons; stopped the fan with the end of a screwdriver; buzzing persisted. And it was definitely coming from within the PSU. Putting load on the GPU and CPU caused the buzzing frequency to heighten, and become somewhat louder. Thinking the PSU was bad; I sent it back for an replacement; new unit came, set it up and got everything running. Was silent and fine for a while (about an hour), but the replacement slowly started developing this problem; the buzzing returned. I tested both units without the GPU, too; same buzzing. That leads me to the final part of my issue. After the replacement had this same buzzing noise; I decided to get a bigger powersupply, since 450W could be considered cutting it fine for a 270X (though I know it's sufficient). So I got a refund and picked up a Seasonic G Series 650W Gold, and a Bitfenix Prodigy. Got all that set up, and installed. Powersupply was silent for a while, but even this unit is now starting to buzz, but not quite as loud as the other two. So I'm thinking, it can't be the PSUs. I've tried different sockets, different cables, extension leads, surge protectors all to no avail. Testing with the case side off revealed that the GPU itself buzzes also; confirmed this as the buzzing changes pitch when looking around in games. So it's got a bit of coil whine, it's not too loud and I can live with it. The noise isn't so much the problem, though. My 270X has been experiencing artifacting in many games, even on the desktop (with Unigine Heaven running in the background in Windowed mode), leading me to believe that the GPU or PSU is causing it. I pulled the 270X out and tested it thoroughly in my main rig; absolutely fine as far as I can see. Also, there is a slight buzzing from all three units even when the unit is switched off, but still plugged in. So I have some questions for those who are knowledgeable on the subject, or have experience with this kind of problem, also TL;DR: 1) Can components other than the PSU, cause a powersupply to develop an irreversible coil whine or buzzing? 2) Is buzzing from the Graphics card and powersupply dangerous, can it cause GPU erroring/other problems? 3) Can buzzing from a powersupply be normal behaviour? Any advice would be very much appreciated, thank you!