Well, given that neither hard drives nor SSDs have any effect whatsoever on internet transmission speeds, my guess is that there is some other factor at play here.
Can I ask, what are you using to measure network speed here? I'm kind of guessing that you're using one of those browser-based speed-measuring websites. I know that some of them work by uploading and downloading a sequence of files, and can therefore end up measuring your combined network and file handling speed, rather than network speed alone...