Re: erratic touchpad when AC charger is plugged

I have found this to be common with several brands of laptop, especially with the cheap Chinese adapters sold on Ebay. You can either use a USB mouse or try adapters till you find one that works. If the adapter came with the laptop, demand a new adapter from Dell. If buying another, try to get a genuine adapter made for that particular model. You may fix it by earthing some external component of the motherboard. For example, touching the serial port with one hand may earth it sufficiently for the touchpad to work but this is impractical. The problem lies with the design of the adapter. I recently had an Inspiron which had this problem with the PA-10 adapters sold on Ebay; correct voltage and current and even listed as suitable for this model. Only the correct model specified by Dell for this model laptop worked.