I've found that I occasionally get a much smaller hash rate than my actual one displaying on the website. For example, multiminer is reporting 230 - 250 khs, but hashcows has thought I've been 50 - 100 for the last two days.
I really want to keep mining here, so can anyone give me any ideas on why this might be? Thanks!
The hash rate displayed on the website is just an estimate based on how many shares you've submitted in the current round. It isn't really important; if your mining software is reporting 230-250kh/s and you have no hardware errors and a small amount of rejects then everything is fine.