My memtest software doesn’t support my 32-bit CPU

Hello Techyv.com!
I have here an old PC, and I noticed that it is running slowly for the past few days. Now my friend told me to use memtest for my laptop to test if the RAM were still working well. Now I've downloaded its version 4, it says it could support both 32-bit and 64-bit CPU. But why it won't work for me? Please help me. Thanks..
