What's the best site for laptop repair such as R/R a motherboard in an HP Elitebook 8440p

If you have basic mechanical skills it is not that hard to do.  If you are in the DFW area I can do it for you.

One of those youtube videos would be good, or any site delineating how to take it apart.  What is DFW?

Dallas/Fort Worth Texas
dbrunton's post's first link is to the service manual

Ok I replaced the board and tried powering it up.  It powers up, all the lights on the bezel come on, but nothing on the display.  Not sure if I hear the HDD working either!

As long as you have all the cables seated properly you may have another bad board.  Lights on and no display was a common symptom on the DV series HP laptops.  There was a big class action over it.
That said I would remove the hard drive, DVD drive battery, wireless card etc and one memory stick and see if you can get something on the display.  If the display works then start adding things back one at a time until it quits to find the bad part.  If you remove all the above listed things and still get no display then swap to the other stick of RAM (assuming you have 2) if still no joy you probably have a bad board or bad processor.
What was the symptom before you replaced the board?

I've had bad disks, bad memory, bad DVD drives and bad main batteries & bad CMOS batteries keep laptops from POSTing.
You could also try attaching an external display to rule out your LCD.  If that model has a seperate video board that could also be a problem.

- There are two sodimms.
- This problem was similar to the other issue but i tried an external monitor and got nothing either.
- I'll try the other troubleshooting stuff on Monday.  

It's amazing how many bad displays, cpu's, and boards we're going thru.  HP's going to pot!

Took out the HDD, Wireless card, CD, Battery, one sodimm, and tried to boot and nothing again.

I plugged in an external monitor and got the login screen.  I know I didnt forget to connect the display cables.

By the way joelsplace, which "DV series" do you mean?  Does that include the 8440p that Im working on?

I don't know how many models were a problem.  They all had nVidia chipsets that desoldered from the motherboard.  The ones I've had trouble with were DV2000, DV6000 and DV9000 but there were others and other manufacturers that had the same problem with nVidia including Apple.  Here's the info:
http://www.maximumpc.com/article/news/nvidia_gpu_settlement_reveals_all_affected_notebooks

If the monitor comes up but not the laptop screen that is pointing at a failure in the laptop screen area somewhere, LCD, backlight, inverter etc.

Looks like I need to try a different display.  
Is there anything else I can test on the board?

Don't think so.

If the monitor works then try the hard disk, CDROM drive, extra memory in the machine and verify everything there is OK and the system does what it is supposed to.

Then presuming your connections to the laptop screen are OK then try and identify what component is failing.  Check the obvious first, brightness and contrast controls (if there) haven't been turned right down.

There are various internet guides for troubleshooting the screen eg http://www.ifitjams.com/lcd.htm

Yes, an external monitor shows that the HDD is fine and the rest of the laptop is working.  No brightness controls I can find.

On the models with the bad boards you wouldn't get an output on an external monitor either.  If yours has CCFL backlighting you could have a bad bulb or inverter.  the models with CCFL normally have a two wire (white and pink) connector that plugs into the display.  If that isn't plugged in you will get a display but it is so dim that it's almost impossible to see.  If you can just barely see the display it's the backlight (bad bulb or inverter).  If you don't have the pink and white wires then you have an LED backlight which shouldn't give you any trouble.

Another thought- any display made in the last 10+ years won't be dark even if the brightness is turned all the way down.  You should have a combination of an fn key and one of the F1-F10 keys that will turn the brightness up and down.  You should also have one F key that will switch the display between internal, internal + external or external only.  It could be stuck on external only.

If it was stuck on ext. only, wouldnt I see at least the bios screen, though?