Re: DG-87 Bottom Power button Flicker
I can confirm it's disk activity. I have the X99 FTW K motherboard and there's a power button ON the board near the 24-pin that flickers with disk usage. Both the front power button on the DG-87 case and this button flicker or stay solid in sync.
If you have a large file or say, an album of pictures, copy it/them, watch the front light and paste them to some temp location. You'll immediately see the light start to flicker.