Currently I am running a set-up with 2X4GB for 8 GB. I am using these. I have been playing Watch Dogs and have had problems running out of memory. I suspect it is mostly Ubisoft's fault and there are probably memory leaks. I always planed on putting more RAM in when I got more funds so now seems like a good time to do it. I am currently looking at this pair of 2X8GB. They have the same exact timings and speed so would I have any problems using them with my 2X4GB for 24GB overall? I plan on selling the old pair to my roommate when he builds his new rig but in the mean time would I have any problems running these together?