Re: bios or cpu-z, which is wrong?
First, you're on the SPD tab which only shows the JEDEC standards and rated specs for the memory modules, use the Memory tab to see what they're actually running at. Second, CPU-z recognize the RAM as PC2-6400 because that was the JEDEC standard found on the SPD. The highest JEDEC standard for DDR2 modules is 800Mhz 5-5-5-18, i.e, PC2-6400, and anything above it is considered OC.
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