How do I check if my my dell latitude d820 is getting power past the power jack?

SOURCE: Dell Latitude X1 will not power up

This is a common problem for all laptops.

The issues you're experiencing all point towards a bad motherboard.

There is very little that you can do yourself other than trying to boot the computer with no battery and reseating the memory.

Try these two options first, write back, and then we'll proceed from there.

SOURCE: My DELL Lattitude D820 laptop is not detecting battery

indicates that battery needs to be replaced. Update BIOS if applicable. If no go and battery is within warranty (Dell warrants battery for only one year of its invoice date), contact Dell for replacement. Otherwise, get a new battery.

SOURCE: orange blinking power light on Latitude D820 laptop

sounds to me like when u lost power it surged and froze your battery and now your battery has dead cells honestly the best thing to do is get a new battery

SOURCE: dell latitude d820. press power button. no

This may be a really stupid question, but you could have overlooked it... Are you sure the power cable is attached to the laptop correctly? It seems like it's just short of power.

SOURCE: Dell Latitude D620, Black Screen/Power On

It is the backlight! That laptop uses a fluorescent lamp. It is bad.
If you look carefully at the screen, you will see the Windows desktop (or whatebver you are running). It just needs to be lit up.... from the back. Tel them to replace the LCd screen or replace the lamp.

Hope this helps!

Testimonial: "Has happened a couple dozen times. Next time the screen blacks out I will look carefully to notice if the desktop is showing. THX"