Did you guys noticed whistling sound this mobo makes when you set CPU VTT Voltage to something like 1.5-1.6v? It's very annoying and loud, I can't seem to find where it's coming from.
Unfortunately Yes. The sound seems to be memory related, getting loud everytime it's stressed. On mine the whistling was most noticeable doing something like a blend or memtest.

Yes but you will take a big hit in memory bandwidth, I would recommend trying to tweak around theses functions on fast.
Yes, v.true. However, I did find that blend stable was very difficult to achieve on fast. Especially at cas 4. Just my experience

What do you mean buggered??? You broke it and how? Or just a problem with defective board?
Oh no what happened
Board just started playing up.

First indications were memory problems, slow pi runs, memtest failure etc. Thought the board had killed my ram.

Took it back to the shop. They did a great job, spending a good hour or so testing everything.

Tested my Gskills in a DFI 965 and they're just fine , but the board's a dud

Just thinking aloud here. need.for.mhz mentioned the whistling sound at 1.5-1.6vtt. Hope this isn't related to my boards failure.

The quads need 1.5v+ to run stable. I almost corrupted my OS trying to run lower than that.

Makes me wonder whether DFi actually tested quads out or not? Given the late release they certainly had time

Hopefully better luck on the next one. Took two IP35 pro's before I got a good one

RLM