maximum supported cpu and memory for qnx 4.25

I am looking to upgrade hardware in old qnx4.25 system.
Is there a maximum x86 Pentium 4 CPU speed for Qnx4.25. Likewise memory, is there a maximum number of GB supported ?

Speed not a problem although if some software ask for process speed they may get wrong value.

Memory addressing is 4G, but that means memory above 4G can’t be access hence the OS has access to around 3.3 Gig of ram.

Thank you, I’ll proceed with my upgrades.