Is Metatrader Tester working faster on 64 Bit OS then 32 bit OS ?

no it is not. the processing speed actualy is dependent on the feed rate of the data. even a 600mhz computer is fast enough to run metatrade without losing data as it samples faster than the data feed.

With Tester, you are just reading from historical files on disk. How is data feed rate and sampling speed relevant in testing?