Alienware M17X

Hi, I have an older M17X that was manufactured in mid 2009 and it came with the standard 2x2GB memory a total of 4GB, I went to Dell's website and entered my tag number and the only memory upgrade for this is the 2x4GB a total of 8GB and the website gave me the info for the memory upgrade and it was as follows - DRAM - DDR3 SDRAM SODIMM - 204PIN NON ECC DUAL RANK UNBUFFERED 1600MHZ PC3-12800 1.5V and I went ahead and ordered the G.SKILL F3-12800CL9D-8GBSK ---- DDR3-1600 PC3-12800 4096MB X 2 CL9-9-28 SO-DIMM and the laptop is not recognizing the memory cards and when I turn it on the fans turn on and the screen stays black and the 'Tab' light starts blinking non-stop and nothing happens and I re-installed again and the same thing happened. Please help