Neoseeker has published a review of ATI's X1900XT 256MB card.

Except for the memory size, the X1900XT 256MB is identical to the X1900XT 512MB edition launched last year: identical 625Mhz core clock and 1450Mhz memory clock. This makes the X1900XT 256MB a very attractive part in the sub $300 USD pricerange. We take a look at noise, power consumption, and performance against the logical competitors, including the X1900GT and X1900XT 512MB to see whether losing the 256MB of memory has any significant effect on gameplay.

X1900XT 256MB Review