It seems to be spitting out enough pixels at 16bit to cover the screen twice over, just interlaced and possibly a bit truncated on the vertical axis.

The overlap shift going from 8 to 16 bits at 1152 x 870 makes me think there's a timing issue that might be alleviated with the crystal swap . . .

. . . that or the whole thing will go down the toilet.

We're talking an oscillator speedup of something on the order of 7 hundredths of a percent. That just might do it.

However you're right, the RAMDAC is indeed a different part:

24Xp___RAMDAC = Bt473KPJ80 - 770 9348 E

24X____RAMDAC = ADV473KPJ110 - (Delta Symbol) 9408 - OF27527.1

24AC#1_RAMDAC = Bt473KPJ110 - 150 9322

24AC#2_RAMDAC = Bt473KPJ110 - 148 9322

The two major ASICS appear to be identical across the four cards, but for date/batch coding, like the second group of numbers posted above.

I'm off to play with the de-soldering & soldering irons . . . lata! [}] ]'>