Kingston KTA-MB1066K2 - 4G Apple Memory Review :: Features

So what's the difference between laptop memory and desktop memory? Generally, the laptop uses memory in a smaller form factor than desktop memory as the laptop uses a form factor called SODIMM instead of a DIMM. SODIMM stands for small outline dual in-line memory modules and are roughly half the size of a regular Dual In-line Memory Module used in a desktop computer.

SO-DIMMs have 72, 100, 144, 200 or 204 pins. The 72 and 100 pin packages support 32-bit data transfer while the 144, 200, and 204 pin packages support 64-bit data transfer. Regular desktop memory comes in 240-pin packages supporting 64-bit memory. Otherwise the desktop and laptop memory are identical as the clock speeds and voltages of both are identical and capacity of SO-DIMMs are the same as DIMMs.

SDRAM or Synchronous Dynamic Random Access Memory has been in use on the PC since 1993. DDR memory or Double-Data Rate synchronous dynamic random access memory doubled the bandwidth of single rate SDRAM by transferring data on the rising and falling edges of the clock signal without increasing the clock speed. DDR memory topped out at 400MHz and was soon replaced by DDR2 memory.

DDR2 memory doubles the bus clock multiplier on the memory thus doubling the data bandwidth compared to the same speed DDR memory. DDR2 memory has higher latency at the same speed as DDR memory s four bits of data can be transferred every memory clock cycle instead of two on DDR and one on SDRAM.

The Kingston package uses DDR3 memory, the latest in laptop memory technology. DDR3 memory multiplies the base clock x4 thus offering 8x the bandwidth of SDRAM at the same clock. Kingston clocks their KTA-MB1066K2/4G memory at 1066MHz. This provides a memory bandwidth of 8500MB/second. The memory formula is 133 (Base clock) x4 (bus clock multiplier) x2 (Data rate) x64 (number of bits transferred)/8 (8bit/byte). The kit comes in a plastic wrapper with two SO-DIMM modules each with 2GB of memory on it.

The Apple MacBook line of computers moved to using DDR3 memory in late 2008 along with the Core 2 Duo Mobile CPUs. The latest MacBooks have two SO-DIMM Slots, allowing for up to 8GB of DDR3 memory to be installed in Dual-Channel mode. The Kingston kit would replace the memory installed on the MacBook in both slots, effectively doubling the amount of memory of the MacBook's default configuration. To install the new memory is a simple process that I will cover here. After all, what's the sense of buying new memory if you can't install it?

First step is to make sure the MacBook is off by shutting it down, disconnecting the power adapter, Ethernet cable and all other cables and remove the battery by pushing down on the memory access door latch to open the access door, pull up on the battery tab to remove the battery. At this point there is a L-bracket that needs to be removed by unscrewing three screws with a Phillips head screwdriver. Once the L-bracket is removed the memory slot levers come out when you remove the bracket. Remove the installed memory module by moving the lever to the left and pull out the memory module. Installing the new memory is easy. Insert the gold edge first with the notch on the left side using two fingers to push in the memory modules. The levers should close. At this point re-attach the L-bracket, re-install the battery and close the access bay cover. The memory is installed in pairs on the MacBook Pro 13" one on top of the other so installing the memory on the bottom first is important.