System is a netbook...which has certain implications, IMO.
a. System is not intended for upgrading key components.
b. System is not intended for heavy computing, is not designed/assembled in the same manner that a laptop designed for power computing, gaming, etc. might be designed. My understanding is that netbooks are intended to be used primaerily for lmobile, ight computing needs and Internet accessibility.System Specs
Soooo...my questions would be what are you trying to run on this system?
Please...Publish a Snapshot using Speccy - http://www.bleepingcomputer.com/forums/topic323892.html/page__p__1797792#entry1797792
I'm not a knowledgeble hardware person. so take all that I say with that knowledge
As for changing the drive to an SSD and installing the max that the system supports...neither of those things should contribute to perceived system slowness...with the possible exception of your adding RAM that is incompatible/slower than the original RAM installed.
Any number of things can slow a system down in actuality...and your perception of a slowdown may also be an erroneous perception. As long as the same apps are installed now as compared to the period to which you are mentally comparing performance and no other factors have changed that can result in a differential...performance should be at least just as good.
If you post the Speccy link, we will be able to make somewhat better guesses at what is going on.