I want to get the more performance with my gaming computer. I have been using the Intel D5400XS skulltrail gaming platform for my PC. I decided to add the extra 2 FBDIMMS in my skulltrail. Now my upgrade totals to 10 GB (i.e. 2 x 1GB and 4X2GB). After completing the replacement task I went to see the performance of it. It works good as I assumed. Later I have noticed that there is a little variation in memory performance. How could this happen? is there any problem with mixing up the different sizes of FBDIMMS ?