"did they up the core by oc'ing it?"
well if you consider that every company does this, then yeah, they did. AMD, Intel, nVidia, and 3dfx ALL try to put the chips that aren't capable of high speeds in low cost parts. they can make more money off them if they fail the standard test this way.
notice that the RAM is also 5.5ns, that means, that it is NOT overclocked.
BTW, most Voodoo 3's could hit 183 with a good heatsink (and some needed a fan). the Voodoo 4/5 series chips aren't too different from the Voodoo 3 chips, so it's not surprising that they can hit 183 mhz (hey I can get my Voodoo 3 2000 (default of 143mhz) up to 200mhz with no crashes if I add a fan!).
so this increase in mhz gives us how many extra Mpixels? 136.. ehh. that's ok I guess.
FSAA is great man.. I gotta see if 8X helps or not.. now I can't live without either extremely high res, or FSAA.
did you guys see the firingsquad benches with the 3dfx 1.03 drivers? they showed a measured improvement where fillrate matters (FSAA, and high res). take a look. I'm willing to bet that this monster will be able to hit 1024X768X32 with 4XFSAA at around 60FPS (perhaps a bit lower). that'll be sweet..