M6600 running Windows 7 keeps turning itself on.

Hello,

I have an old Dell Precision M6600 workstation laptop running Windows 7, still in pretty good shape. In the past I had upgraded the hard drive to an SSD, added more memory, added a second SSD and a solidstate memory card, I think its an eSATA card. 

Everything seemed to work well until recently. I did changed my set up so I can use an external monitor plugged to the HDMI connection. About two weeks ago I noticed that my laptop started to turn itself on. I normally shut it down when finish using it. It would shut down, like normal. I started noticing a white LED on along the side of the laptop. When I opened the lid it would come to life, like I had put it to sleep instead of shutting it down. I did noticed when I was backing up all of my files onto an external drive that the laptop was being attacked. My anti-virus software was popping up notifying me that it had blocked a virus attack. This happened several times. Later I ran a complete scan but nothing came up. I eventually turned off the wi-fi. Maybe a virus is causing my laptop to switch on?

I did a search about the laptop switching on and I found that there could be a short or maybe internal contamination causing a problem and the laptop needed a good cleaning. I used my can of pressured air to blow out any dust and particles within the laptop. I also taped down two loose wires with connectors (I think these are for connecting a WLAN card). After doing this I placed back the battery back on the laptop and plugged in the external power supply. I left the laptop shut down over night. The next morning I noticed the LED on again. I opened the lid and it woke up. I've not switched on the wi-fi.

Any ideas of what can be causing this?

I purchased this laptop from new back in 2013. I have some software that I want to keep using and I really can't afford to by the latest versions. I use the laptop mainly for hobby work (creating 3D CAD stuff for crafts, art and to send to my 3D printers). For my freelance business I did purchase a new Dell workstation laptop running the latest version of 3D CAD software. This one I use for serious business work.

Any help is appreciated.