I picked up a Dell XPS8900; 17 6700; 16gb; GTX745 2gb with a 1 TB HDD. Long story to get me into a Dell which I will skip. Anyway I moved the mobo to a new case with a Corsair 850w psu, 3 hdd, 480gb PNY SSD, GTX960 4gb; Swiftech fan block, Win10 Pro 64. I get a white screen error message stating "imminent power switch failure." Hit continue and it boots up fine. I have found the power switch pins on the f-panel 1 block (3 pins in from the right - vertically}; hdd led top two right pins and I have jumper pins 1, 2 & 3 as with the original socket (don't know what these do). Case is a Diablotek V3 and does not have a power led since I think the front fan leds act as the power light. Reset button is not used. So how do I get rid of the error message on power up? Anyone have a pin out for f-panel 1? Is there a set of speaker pins there? Thanks.
There's not going to be a way to disable or suppress that error short of reconnecting the original switch block. You really have two options:
Put the board back in the Dell case, and use it that way -- or, complete the "home build" and replace the mainboard with an aftermarket unit and standard wiring. That will also require a new heatsink-fan assembly and it will also require buying a retail license for Windows 10 (the OEM one won't work with a non-Dell system).