my goal is to open any software in a second and extract files very fast. i thought that extracting winrar files will be super quick but it is still taking some time and not every games loading faster than on regular 7200 RMP hard drive for example Pro Evolution Soccer 2010.
Adding another drive will not benefit random access time. It could improve throughput.
winrar probably depends on a mix of HD performance and processor performance. What processor do you have, and if you look in task manager, is it maxed? (I don't know if winrar takes advantage of multiple cores, so the question might be, is one core maxed out?)