well if you have the Athlon 3200+ XP processor, then your CPU External clock needs to be set at 200MHz, you're getting confused in your manual when it says multiply it by two. They are referring to the RAM, so basically your RAM is running at 200MHz when the CPU External is set to 100. Set your CPU External to 200MHz, look around and see if there is a multiplier option. It should be right below the CPU External Frequency option or atleast near it. If you don't see a multiplier option, then your BIOS simply doesn't have that option. All in all your CPU External needs to be set to 200MHz and the multi should default to 11 to give you 11x200 = 2.2GHz which is exactly what a 3200+ chip should be.
If your only settings for memory are AUTO or By SPD then put it on By SPD and that basically means it'll adjust the memory to the speed of the CPU or atleast attempt to. That should hopefully give you a 1:1 ratio with your CPU and RAM, assuming you have PC3200 RAM. You see the PC3200 RAM is 400MHz, and by settings your CPU External to 200MHz that's where you multiply the double data rate. 200x2 = 400MHz RAM.
So make sure your Vcore is at it's default 1.65, check for a multiplier to be set at 11 and make your CPU External 200. THen change the memory timings to By SPD and that should clock them together.
If you see the options under RAM Timings for the frequency that say (133,166,200) then you want to set it to 200 because 200x2 = 400MHz, some BIOS's will show you the Frequency after it's already been multiplied meaning instead of seeing the options I just showed you you'd see the options (266,333,400) so basically so you know 133=266, 166=333, 200=400 when it comes to RAM timings. Hope this cleared somethin up for ya