Thank you for writing .
only two pieces of RAM .
In this case , Dual Rank or Single Rank, either should not care .
It is written with [(Single side) SS] to [(global) Asrcok].
http://www.asrock.com/mb/AMD/FM2A88M% 20Extreme4 + /? cat = Memory
>> DDR3 2400 4GB A-DATA AX3U2400W4G11-DMV SS 2pcs 2pcs v
That you have the following meaning , you do not understand .
It does not say that you are familiar even to [ADATA].
BIOS (UEFI) , was carried out (Jumper short) CMOS clear.
Is running at the (Default) JEDEC 1333 now .
For a product that has just been released , it is very information is insufficient .
In Japan, the short supply as before. We repeat the situation that already sold out when it also purchases of stock in information such as Twitter , it was confirmed . Even amazon, you can not get surely still in short supply .
By the time this issue is resolved , I hope that you have solved all the problems such as this .