Thinkpad X61s Asymmetric or Symmetric Dual-Channel

I made a simple test with Memtest86+ how much asymmetric and symmetric dual channel modes differ in transfer speed:

Asymmetric:
Memory: 3046M - 2716MB/s (mean out of 3)
Symmetric:
Memory: 4022M - 2836MB/s (mean out of 3)

So that is 2836/2716 = 1.04418
Which means symmetric dual channel in the X61s (Intel GM965) is (synthetically) just about 4.4% faster in terms of transfer speed than asymmetric dual channel.

Used were 2x 2GB Kingston CL5 modules for the symmetric test. 1x 1GB Samsung CL5 and 1x 2GB Kingston CL5 for the asymmetric test. The 1GB was put in the second slot for the asymmetric test.