VIA C3 Ezra, Nehemiah, Samuel...how do I ID them?

[Tetrium]

I've got a small handful of these chips, but I'm having trouble identifying what version C3 they actually are.

Anyone know how to correctly ID these chips?
Visual doesn't seem to always work (Samuel and Samuel 2 seem to look identical) and the CPU voltage isn't always printed on the chip.

Anyone know of a reliable way to visually ID these chips?

[Neon_WA]

CPUShack's page on VIAs may help a bit
http://www.cpushack.com/VIA.html

if the voltage isn't on the top of the processor, it should be listed on the die cap

[Tetrium]

Thanks.

The chips I'm trying to identify are:
VIA Cyrix III 550 (probably a Samuel)
VIA C3 700 2.0v (Looking at the voltage, it should be a Samuel, not a Samuel 2 as indicated by the print on the top)
VIA C3 866 (1.4v but no little resistors on top of the CPU package. From the voltage it should be a Nehemiah, but Nehemiah starts at 1Ghz?)
VIA C3 1Ghz (1.45v and lots of those resistors, should be Nehemiah)
VIA C3 1.2Ghz (1.45v and many of those tiny resistors, should be Nehemiah)

I'm kinda hoping that one day I find a PGA C3 1.4Ghz, but the C3's hardly ever appear for sale.