Inspiron N7110 does not power up

You've pretty much isolated the problem to a bad mainboard -- given the age of the system, it may make more sense to replace the system than to sink a few hundred dollars into a replacement board for this one.

Reconditioned motherboards are available but the prices range all over the place.  There are several models with different components but I have not been able to identify the model in my laptop.  If it is one of the cheaper ones, I might spring for it (This is an extra computer).  I entered the service code but couldn't find much information.  I suppose it would be identified on the motherboard itself.  Thanks for the input.

There are two basic designs:

Integrated video (Intel)

Discrete video (AMD/ATI or nVIdia).

You can replace same for same with no additional parts needed.

Moving from Intel to discrete will require a new heatsink assembly and a minimum of a 90W power adapter (more for an i7 CPU).  65W will power the Intel system - not the discrete.

Thanks for that information.  My sales order from 2011 shows "Intel HD Graphics/ HD Graphics 3000 with up to 1.6GB Dynamic Video Memory".  I am guessing that is the Integrated video (Intel).  A couple of places are listing refurbished motherboards for $139.  Would be interesting to see if I can make this computer work.  I really don't need another "new" computer.  Thanks for your input.

I have looked for Intel motherboards for the N7110 and see most frequent part numbers for sale are XMP5X and 7830J.  I looked at the original parts list for my computer based on the Service Tag and did not see either of these part numbers nor did I see any part number which I thought would appear to be the motherboard.  Of course, I didn't know what I was looking for.  Are Intel motherboards for this model interchangeable or do I need to be specific.  I am guessing I need to be specific. I am guessing that the part would is maybe part of the category labeled "2nd generation Core I 5-2. and possibly the "Module processor which is part 4NM9Y.  I am way over my head here.  If Dell techs are reading this, the Service Tag is B99SQ1.  Thanks for any guidance.

 You may be able to find the motherboard part number under the ram chips, or just go to Dell.com and put in the service tag number for the laptop. The system board part number may appear under original configuration, or something like that.

This is a long shot, but try it! remove the battery and power. Hold down the power button for about 30 seconds, then release it. Plug in the AC adapter without reattaching the battery, and see if the laptop comes back to life. This process sometimes "resets" systems and dissipates static electricity from the system board. If this does not work, as other here have said, the problem is more than likely the motherboard.

Yes.  Thank you.  Thanks to everyone who responded.

Thanks.  No joy, however.

What about the motherboard battery, CR2032 3-volt coin cell battery (separate / different from the power battery)?

Thanks,  Good idea.  But the old battery stills registers 2.45 volts.  Should be sufficient.  New battery registers 2.75 (new 3.5 volt battery).  Waiting for Amazon to deliver a used motherboard.  The difference in the voltages may be my testing equipment or just my inability to get a good reading.