Solved: Is 600mhz Ram same as PC 6200 ram?

I have 2 sticks of 1gb 800mhz each ram on my computer thus 2gb ram in all.

Now I bought another set of 2 sticks of 1gb PC 6200 ram to add to the same system.
The store didnt have the same type of ram I have on my system ( 800mhz ) so they told me this PC 6200 sticks are same as 800mhz just that different manufacturers write either the PC6200 or the 800mhz.
On adding this ram, I notice slowness in response from the system.

Any ideas whats happening? Is it true that these PC6200 and 800mhz Ram are same in speed?

Appreciate your answers

 

Triple 6, you're very right. It is PC2- 6400. After getting your response I checked the package and noticed it says PC2-6400. So I assume PC2 6400 and 800mhz ram are just the same speed. Thanks for responding.