help me determine my ddr2 ram speed

[meeeeeeeeh]

So I just bought what seller said it was 800mhz DDR2,but when i opened task manager in performance tab it says that memory speed is 667mhz. I mentioned it to him and he said that they are definitely 800mhz.

here's the pic from task manager and cpu-z, for some reason cpu-z is showing 438mhz?

I checked the bios and dram frequency is set on auto.
Im not really sure what else to check or if im reading something wrong, any help?

edit:
Modules are:
2x QIMONDA HYS64T256020EU-2.5-C2
2x samsung m378t5663qz3-cf7

 

[The Paladin]

Q: what is the make and model of your motherboard ?

your Qimonda is HYS64T256020EU-2.5-C2 Qimonda 2GB PC2-6400 DDR2-800MHz
Your Samsung is M378T5663QZ3-CF7 Samsung 2GB PC2-6400 DDR2-800MHz

So both set of ram are 800Mhz ram and will show about 400-450 depending on motherboard and that is because DDR stands for DUAL DENSITY so its 2x400MHZ, therefore what your reading is correct

 

[meeeeeeeeh]

Mobo is asus p5qc .

So everything is fine then? Why is task manager showing 667mhz though?

 

[CountMike]

Windows don't get that right all the time, that CPU-ID is right.

 

[lordmogul]

CPU-Z shows it right.
The memory bus frequency is noted as 438 MHz, and since it is DDR memory that results in effective 876 MHz.
So it is not only running at 800, it is even overclocked to more (according to GPU-Z)
Depending on the quality of the cips shat should be not even an issue.