Since all the Dells I know power up with some BIOS or other signal, this is usually a failed hardware issue.
Try other than sleep now. Try Hibernation to see if you can avoid a repair counter.
After I put my dell desk top to sleep. I wake it up and the computer comes on but i get no signal through the monitor. I end up having to turn the computer off and then turn it back on to get a video signal. Please help. Thank you

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