Mixing different RAM (same manufacturer/speed)

I'm guessing its not a brilliant idea, but here goes,

I have 6GB XMS3 Dominator TR3X6G1600C8D (3x2GB) bought a few years back with a i7 rig, (Asus P6T Deluxe). I now want to up the RAM and its not available from Scan any more, they however have some Corsair XMS3 TR3X6G1600C9 (3x2GB) on Today only for £60.

They are both 1600MHz, but different latencies

Corsair XMS3 Dominator TR3X6G1600C8D 8-8-8-24 at 1.65V VDIMM
Corsair XMS3 TR3X6G1600C9 9-9-9-24 at 1.65V VDIMM

Can I buy the TR3X6G1600C9 to work along side my TR3X6G1600C8D?

Thanks,

PaulG.

i did the same, they will not work at xms ratings though, the timings cannot be that tight on 6 sticks so leave it at default settings.