memory test question

Hello everone: As I'm not a techie, this may appear to be a stupid question but, as someone once said, there are no stupid questions, only stupid answers. I'm running SuSE 9.1 professional 64-bit on an AMD Athlon 64 on an Asus K8V Deluxe motherboard. I'm currently running the memory test [ Memtest-86 v3.1 ] found on CD # 1 [ 32-bit package ]. Given that the CD is for the 32-bit program, is this test valid on the 64-bit hardware or does memtest simply test the hardware regardless of the processing power of the CPU? In other words, does the fact that it is a 64-bit processor invalidate the test results? Any help greatly appreciated. Cheers, Mike