Chuck Guzis wrote: The "half good" memory dates back long before 256K chips--it goes all the way back to 16K ones. I've got a batch of Intel 2109s that differ from each other by a suffix -1 or -2. The idea is that the suffix indicates which half is good; otherwise the chips are electrically the same. I remember when the local Intel sales guy dropped off a bag of the things on my desk and I sorted through them and found a batch where all 16K worked in my application. Cheers, Chuck ------ Billy: Actually it goes back further than that. Intersil offered the 6002 (a 2K Dynamic RAM) with options of 1K good. I never saw it on smaller chips like the 256 byte or the 1K. But it would not surprise me. This was the era when a new state of the art memory chip was $15-20 each and in very short supply. A half good part could be very useful in a terminal or small system. By small, I mean 4K or 8K bytes, typical of many memory boards available in the early 1970's. Billy