It seems to be getting harder to find the 512KB SIMMs. Someone want to run some off using these:
http://www.ebay.com/itm/271605768758?_trksid=p2060778.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
TC524258?
These are the chips the original VRAM are built with, but in a SIP package instead of SOJ. I'm not sure one could get the SIPs to sit flat enough, but that's a good price on the memory.
Alternatively, I think one could use these (KM4216C256) to build a VRAM SIMM. These are the chips that were used on the PCI PowerMacs 1MB VRAM SIMMs, but they seem to have the same functionality, just 4 times wider, as the original chips on the 512KB VRAM:
http://www.ebay.com/itm/131219842210?_trksid=p2060778.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
http://www.ebay.com/itm/271605768758?_trksid=p2060778.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
TC524258?
These are the chips the original VRAM are built with, but in a SIP package instead of SOJ. I'm not sure one could get the SIPs to sit flat enough, but that's a good price on the memory.
Alternatively, I think one could use these (KM4216C256) to build a VRAM SIMM. These are the chips that were used on the PCI PowerMacs 1MB VRAM SIMMs, but they seem to have the same functionality, just 4 times wider, as the original chips on the 512KB VRAM:
http://www.ebay.com/itm/131219842210?_trksid=p2060778.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT