I went to turn on my laptop this morning, and it very visibly had power, but did not show any power to the screen, and the keyboard did not behave as it normally would e.g. the num/caps lights flashing once and then continuing boot as normal. Instead, the leds are continuously on. When I had this issue before, (and I am not sure this is what solved it) I had been running my display through the HDMI port and onto a television. The issue had appeared when it was not connected, and when reconnected it put everything back to normal. I have ruled out drive problems as it still appears when the drives are removed. Charging and power function appears normal, I have also tried removing and replacing the battery. I recently installed two new RAM sticks as well, but this problem predated them. Any advice?