Reduced Windows Experience Index Score when adding memory


Hello Tony.

I came across your site looking for an answer to a question I have and you seem to be the man to ask. I am running Vista Ultimate 32-bit on my machine. All things being equal, when I run only 2GB of RAM I have a Windows Experience Base score of 5.0. Adding 2 more gigs of identical Ram dropped my WEI to 4.5. It seems adding the extra 2GB of RAM made my memory operations per second drop a half point. I read your article on Maximum Memory in 32-bit Windows ( and the follow-ups but it doesn’t quite answer my question which is this; how come adding more RAM slows my PC rather than speed it up? Thank you for taking the time to read this.


Jonathan H.


I thought about this for a couple of days, and I don’t have an answer for you. I’ve had memory upgrades that increased the heat and power consumption of a laptop, which makes sense, because it needs to send electricity to an additional chip.

Some mother boards will actually increase your operations per second by distributing operations between the various memory chips. My guess is that the reduced operations/sec is a factor of your chipset.

I’ll put this question out to the readers–any idea what’s causing this problem? Please add a comment below.

3 Responses to “Reduced Windows Experience Index Score when adding memory”

  1. Stephan W. says:

    Just an idea – How about it being a latency issue? Maybe this is caused by a downgrading of latency, e.g. (in this example i´ll use an old DDR Ram) the original RAM can do a latency of 2.0 and the new added RAM only does 3.0. THis means the original RAM in the machine that does 2.0 must downgrade itsself to 3.0 because the new added RAM can’t do any faster than 3.0. Maybe this is why you lose half of a point in the WEI??

  2. Peter says:

    When running 4 modules instead of two (even if they are identical latency modules), the latency has to be increased for the modules to work correctly (for example: DDR2-800 4-4-4-12 to 5-5-5-15). I don’t recall the exact reason but, I think it had to do with the additional chips that have to be addressed/accessed.

  3. sukhraj S Bal says:

    how do you change it from DDR2-800 4-4-4-12 to 5-5-5-15 because i have this issue?