There are three main things that came to mind:
1.) The motherboard requires RAM to be installed in like pairs. This is rarely the case outside of RDRAM, but still a possibility, particularly with cheaper motherboards. (It's the same brand, but different capacities and different timings.) You may want to call the motherboard manufacturer and see what they have to say.
2.) The RAM is not up to par, something that may be caught using the free utility Memtest86. You could also try inserting just one stick at a time and running a performance test on each one to report the *actual* read/write speeds, latencies, etc. Off hand I believe the free version of PCMark05 would be sufficient.
3.) It could just be a peculiarity in the design of the performance indicator. Prior to release there were several known inconsistencies, and something may have slipped out the door into the final version.
I'd look into the first two, and if everything comes back OK and you're not suffering a noticeable decrease in system performance I'd let it be. If you are truly concerned you could try upgrading the BIOS (there is an update available) or adjusting the timings, but note that both do present risks, including permanent failure of the hardware. Thus, it may be best to rely on your experiences and not what Windows is telling you.
John
Foxconn K8S755A-6EKRS Socket 754 http://www.newegg.com/product/product.asp?item=N82E16813186069
AMD Athlon 64 Processor 3400+ 2.4GHz
1 x 512MB Corsair Value Select http://www.newegg.com/Product/Product.asp?Item=N82E16820145026
2 x 1024MB Corsair Value Select http://www.newegg.com/product/product.asp?item=N82E16820145505
NVIDIA GeForce 6800
37GB Raptor SATA
Windows Vista Ultimate
When I run this system with 2 sticks of the 1 gig RAM, the WEI is 4.2 based on the RAM memory operations per second. When I add the 512MB stick, the WEI drops to 2.4. I have tried every possible combination in the memory slots with the same results.
Windows and the BIOS recognize the full 2.5 gig, it is the lower WEI that is bothering me. Any thoughts on how to determine if Windows is utilizing the full 2.5 gigs. Do I need to change timings or something in the BIOS?
Thank you.

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