Advice - Can motherboard be upgraded to Intel chipset?

I have an older PowerPC Dual 2.5Ghz G5 tower, with 5GB DDR SDRAM and running 10.5.8. However as it appears people are phasing out support for non-Intel Macs in terms of programming, I am trying to weight my options. Does anyone know whether I can upgrade just the motherboard to allow me to use my tower and components such as video card, HDDs, etc including RAM? Or must I suck it up and buy an entirely new tower?