This is Not spyware or anything like that, it basically tells you all that is on your system. and then if you click the processor (CPU) on LHS it will tell you what the maximum CPU is that you can install.
You can also check your Ram and so forth
Please let me know the outcome of this online hardware (quick) scan.
You will have real trouble trying to make a faster module to work. 900 MHz is close to the top speed you can use on that P3 board. You can get a new Dell for $399. Other PIII processors will have special requirements which are difficult, unless you buy the expensive upgrade from Dell... and they probably no longer sell. it.