I have 2x 2GB of G.Skill 7-8-7-24 then I changed it manually to 7-7-7-24 it did change but my question is why the other things are different, see the image below each timings on each colour are different.
my ram installed on the 2nd and 4th bay of the ram socket.
That is the timing tables, or the recommended latencies for each frequency setting. Your actual speeds and latencies will be shown under the Memory Tab.