Whats the difference between these two?

[Itsmee]

Can someone tell me what the difference is between these two and whether the extra is worth it?
Also if its okay and decent for the motherboard?

thanks for any help.

YOUR BASKET
1 x Corsair Dominator Platinum 16GB (4x4GB) DDR4 PC4-21300C15 2666MHz Quad Channel Kit (CMD16GX4M4A2666C15) £313.99
1 x Corsair Dominator Platinum 16GB (4x4GB) DDR4 PC4-21300C16 2666MHz Quad Channel Kit (CMD16GX4M4A2666C16) £259.99
1 x Gigabyte X99-Gaming 7 WIFI Intel X99 (Socket 2011) DDR4 EATX Motherboard £254.99
Total : £838.57 (includes shipping : £8.00).

 

[snips86x]

CAS timings!

yes, that motherboard & RAM will be fine.

 

[Itsmee]

Thanks for that,
Is it worth the extra spend?