I am looking for compatible 4GB memory modules to run at 1600MHZ on my GA-P43T-ES3G V1.3 with a Modified Xeon Quad X5472 running at 1600MHZ. Right now I have 3 sticks of Kingston 2GB ram running at 1333MHZ I have a 4th stick of the Kingston but gives memory errors in Memtest if I run all 4. The 4GB kits were made at different times but have the same part # (2011,2012) Any way I would like to have 2- 4GB modules for 8GB ( board supposed to support 16GB). The only 1600MHZ 4GB sticks shown in the QVL is a Kingston 12GB set that is not being made any more and if found they want over $200 for it. One vendor told me the board requires double-sided Modules for 4GB but there are very few made. Any help would be appreciated. I tried running the 3 sticks of Kingston 2GB ram I have now at 1600 but noticed the north bridge heat sink goes from 38C (1333) to 50.5 at 1600 ,this is reading the top of the heat sink with digital thermometer.