hi, i will make a GBC overclock mod, and i have recycled two crystals from an old network card, but in the 2 crystals don't say which is the mhz value, only say "R20CE62" and "R20CB72" respectively, i googled it, but i only found the value of the "R20CB72", which is 20Mhz, but the "R20CE62" didn't match any search, anyone know which is the value of the unknown crystal?

photos of the crystals