Vengeance sodimm3 1600mhz Backwards Compatibility

[socgti]

Hi,

I have just bought a kit of two (2X4GB) sodimms 3 CORSAIR CMSX8GX3M2B1600C9 VENGEANCE 8GB and much to my dismay they are not compatible by my laptop a Sony Vaio VPCEB4Z1E. So the nub of the matter is while my laptop is a 1st gen core i5 and these dimms are advertised as backwards compatible, they do not work. Once I put back the old dimms samsung PC 10600 the laptop booted normally in win 7.

Any ideas? I am just about to return them back.

[Greybeard]

For that Intel 1st gen CPU, you will need a kit that is built using 2Gb IC. These are the SKUs that are compatible with your laptop:

CMSA8GX3M2A1066C7
CMSA4GX3M1A1066C7
CM3X4GSD1066
CM3X8GSDKIT1066

[socgti]

So these are not backwards compatible.

Actually even the ones that the laptop has preinstalled are 1333mhz sodimms but they are timed at 1066mhz.

[Technobeard]

There's a difference between backwards compatibility and what's going on here. Memory can be set to higher timings and lower speeds, and most systems will be ok with that. That's backwards compatibility.

What's going on here is that memory controllers have limits as to how big the ICs it talks to can be, and every couple of microarchitecture models, the memory controllers get better and can deal with bigger ICs. Unfortunately your CPU can only handle 2 Gb ICs whereas this memory is made with 4 Gb ICs.

[socgti]

Thank you for the thorough clarification.

I wish I knew that before I actually bought the kit.

The seller does not accept it back for a refund or exchange with the correct kit, without keeping a 20% off the price of the kit that I have bought yesterday.

I am really dissapointed.

[Greybeard]

That's unfortunate that your seller has to charge you restocking fee for swapping out that kit.

Tell you what, go ahead and submit an RMA request on our website and we'll do the swap for you from our side. Just make sure to note in your ticket that you need a replacement that I listed above. Better yet, post your ticket so I can make sure that you are getting the correct part.