3 amber lights followed by 1 white = CMOS battery failure. Change the CMOS battery (coin-cell battery) to a brand new one.  Whenever touching components or working inside a computer, wear a grounded wrist strap, also called anti-static wrist strap, ESD wrist strap, or ground bracelet. It's a cheap and sensible precaution. Rest the laptop on an anti-static mat or at least a reasonable alternative such as corrugated cardboard. (Repeatedly touching a metal case part is not sufficient mitigation with modern components.)
Dear Forum users, Unfortunately I don't know the history beforehand, nor what exactly I did, but I notice that my computer has a lot of problems starting up. The problem starts as soon as I turn on the computer. My indicator on the computer does not light up solid white, but flashes once, followed by 3 orange flashing lights. After this there is a short break in between and it flashes again 1 time white, then 3 times orange. This process repeats. Then the startup itself. I am almost immediately presented with the SupportAssist Pre-Boot System performance Check screen. Also went through the tests on this but he found no problem. Also installed all updates via the Dell update pages and also did the full hardware test. Here too, the computer passed the test without any problems. If the computer submits a request to restart, I confirm it, but 9 out of 10 times it will not start. Then I can turn it off completely and then get the SupportAssist Pre-Boot System performance Check screen again at startup. Rarely does he start the computer without showing the screen. Can someone tell me what exactly could be going on or what I can do about this? Thank you in advance. Yours sincerely, Tommy-C.
XPS 8940, indicator with start up problems