Socket 1156 CPUs, as well as Intel socket 1366 and AMD processors, have an integrated memory controller. All other Intel CPUs use an external memory controller, located on the northbridge chip (also known as MCH, Memory Controller Hub) of the chipset. This means that on this processors the chipset (better said, the motherboard) is the key component that says what technologies and how much memory you can install on your computer.

Since now the memory controller is inside the CPU, it is the processor, and not the chipset, that defines the memory technologies and the maximum amount of memory you can have. The motherboard, however, may have a limitation as to how much memory can be installed.

At the moment, the integrated memory controller of socket 1156 processors supports only DDR3 memories up to 1,333 MHz under dual-channel architecture, however Gigabyte says P55A-UD6 supports DDR3 memories up to 2600 MHz through overclocking. This motherboard has six DDR3 sockets (feature usually seen only on socket 1366 motherboards). At this moment DDR3 memory modules can have up to 4 GB each, but this motherboard "only"  supports up to 16 GB total because it does not support six double-sided modules (i. e. modules with memory chips soldered on both sides), supporting only four double-sided modules or a combination of two double-sided modules and four single-sided modules (which have chips only on one side of the module).

In order to achieve the maximum performance you should install two, four or six memory modules to enable dual-channel architecture. When only two modules are used make sure to install them on the white sockets. If you install six modules, the ones installed on blue sockets must be single-sided. Gigabyte used a simple but efficient color scheme to identify the memory sockets and their compatibility with single- and double-sided modules.

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Figure 6: Memory modules. Install two, four or six modules for the best performance.

Near the memory sockets there is a big power button, which allows you to turn on your computer with no need to connect the buttons from the case. It is a great feature when there is a small button to do this, and having a big one is almost an enthusiast's dream.