Slow laptop loading

A few days ago my laptop started to slow loading. It has Lubuntu installed. Further more when it goes to sleep it can not be retued and I can see only black screen. Sympthoms: slow loading, when lubuntu loaded and I can see login screen my mouse moves like with delay in 3-4 seconds, also it can just freeze and then I need to reboot laptop (but I need to do it a few times).

What could be wrong. Is there tool for testing hardware in such cases?

Also I month ago I broke my touchpad when I was cleaning fans. I broke the place in touchpad where cable from motherboard was plugged in. And then I got it repaired. And repair gay sad that he had to solder some not ordinary cables. So could it be the reason of problems?