I am getting low fps in almost most of the games and iam making sure it is not due to my new HDD. I have some problems with my old HDD and it stopped working few days back.
What is the normal average data transfer rate?
Low FPS will be rarely caused by hard drives. You'd probably be better off posting another thread under the systems section or the graphics section of the forum listing the precise problems you are seeing and your system configuration.
Don't get me wrong though you'll certainly get help if you continue posting on this thread. Posting in another place would just mean more people who are keen on graphics or are more knowledgeable about the topic are more likely to see your post.