Ok so the crystal is 25Mhz and the CPU is 25Mhz but sysinfo is reporting 13.4Mhz?
My card -
http://amiga.resource.cx/exp/professional530plus
Sysinfo has no idea what clock speed your CPU is running at. It just makes a guess based on some timed loops which run at different speed on different CPUs... It probably isn't accurate on anything other than a 68000...