Inspiron 700m Shuts Off When Unplugged From Wall

I have exactly the same problem and I have two new batteries, one Dell and one non-Dell.  I called Dell and they had no idea.  I brought it to Geek Squad and they can't fix anything like that.  Have you communicated with Dell?  It looks like you don't have any responses.

how do you know that will fix the problem.

If you've already tried a new battery and a new adapter (both Dell - NOT third party) to no effect, the mainboard is the only other part that could be faulty and cause this problem.

Same problem with an Inspiron 1300.

Sometimes I'm able to unplug the computer and it'll keep running. That's become pretty rare though, and more often now it'll shut off as soon as I either remove the adaptor from the computer or unplug the charger from the wall.

The computer WILL turn on with the battery -- but I have to unseat then reseat the battery for that to happen. Sometimes I have to do this more than once.  But I never run the computer on the battery, I use the battery only to move the laptop from place to place in the house (never travel with it).

The battery DOES charge up again.

Tried dusting and cleaning the connectors, but that doesn't seem to help.

The idea of replacing the motherboard is ...well, not helpful. I can buy a new laptop for pretty much the same price.

Although maybe there's an internal component that needs to be cleaned?

There are repair services listed in eBay (search on "Inspiron 700M motherboard" ) that will replace motherboard for about $150-$165.  Have not tried it yet, but planning on doing that after Xmas holidays.

I just can't see that as being worth it, not with the prices of brand new entry level laptops these days (and this Inspriron is entry level). You could easily find a good used laptop for that price too. These things just aren't built to last.

My suspicion is that the connectors on the motherboard have gotten fouled up with dust and whatever over time --I don't transport the laptop, just move it from place to place about the house. It's on --and open --for most of the day. Probably the design of this computer doesn't like that at all.

As a test, I blew out the laptop a couple weeks back with canned air (couldn't do a thorough job because the can was practically empty) and that has helped a lot.

Now I'm able to start up the computer off the battery most of the time (sometimes I have to reseat the battery). And when I unplug it, it only shuts off about half the time (sometimes I can start it right up again off the battery).

 I'm wondering if a better cleaning won't do the trick?

In the meantime ... my battery (a replacement) only seems to charge to 75 percent now...

I was having the same problem but it was being caused by a short in my power cord.  The battery would charge, i could run the laptop all day on the power cord or until the battery discharged fully.  However, most times when i would remove the power cord from the laptop, it would shut down.  Swapped out chargers and it hasn't been an issue.

All,

Clean the copper contacts on the battery and on the laptop!!  

I have a Dell XPS, newer model.  I've had it for 2 years with no problems.  I always use battery only when I can so it's not always charging.  But just recently the laptop would shut down when I removed power cord, even though the battery is fully charged.   I cleaned the contacts on the battery and on the laptop with rubbing alcohol and issue seems to be resolved.  I had never removed the battery, and I think over time, the heat from usage does something to the contacts to lessen the conductivity of the copper.   Try this.... it never hurts to clean the contacts!!