The 440ep-flex 800Mhz versions are ok AOS4 starter machines and pci->pci-e adapters and you can use more modern cards but lack 3D due to drivers, my 440ep-flex is the 800Mhz version and I got it quite cheap and put a radeon HD 7770 in it (overkill on the dog slow PCI bus but I had it spare laying around), then a SSD for fast access time.
Works quite good but I prefer my mac mini and morphOS but that's me.