Pretty simple question, please point me in the right direction if this has already been asked.
I am designing a board around freescale's IMX23 microprocessor which runs from an external crystal at 24 MHz. I know that I need to keep the crystal close to the proc, but does it matter if the crystal is on the other side of the board (4 layers)? I know that for routing DRAM traces you want to avoid vias like the plague but would I be okay putting the crystal directly underneath the processor? The traces would be extremely short, but the vias would pass through a GND and VDD plane. The alternative is placing the crystal slightly farther from the proc, about 250 mil.