This is just my 2 cents, but I'd go for the CPU. Reason being you can upgrade RAM later with more sticks. However, it all depends on your use case, as this is the old memory-cpu tradeoff dilemma.
Want speed? Go for CPU. Want to have many tabs open, or guarantee a program does not crash due to low memory even if it doesn't run at full steam? Go for memory.
Many virtual machines open? Definitely memory. Gaming? CPU... most of the times.