How much of a performance hit using asymmetrical dual channel RAM?

Question

As a follow-up to my question Can a P55 chipset support 6GB as 2GBx3?; I understand there might be a performance hit using an odd-number of sticks.

My question therefore is - How much of a performance hit? Would it be perceptibly slower when running heavy process/memory hungry apps?

Answer 1

The motherboard will fall back to single channel mode. See this TechSpot forum post: Dual Channel with 3 sticks of RAM... This is why a 6GB configuration is typically 2x2GB, 2x1GB.

However, as per the Wikipedia article on dual-channel architecture, depending on your applications, you may or may not experience a significant performance difference. Memory-heavy operations may be noticeably slower, but don't expect a very large difference.