The Mephisto Berlin Professional was launched in early 1994, and was available in the UK from May that year. It featured Richard Lang’s Genius 2.0 program and significantly more powerful hardware than the Mephisto Berlin 68000 it replaced. A 32 bit 68020 cpu runs at 24 MHz compared with the 16 bit Berlin running at 12 MHz. The Berlin Pro has double the program ROM (256 KB) and double the hash table RAM (1024 KB). All of the Berlin’s excellent features and game information were retained and the opening book extended from around 100,000 half moves to 180,000 half moves. Altogether a comprehensive upgrading which showed in the Berlin Pro’s chess strength up by around 130 Elo points on the Berlin.
Selective Search magazine had the Berlin Pro immediately vying for leadership of their chess computer ratings table at just below 2400 Elo. (Note: Chess computer ratings 20 years ago were significantly higher than they are now). However by Spring 1995 the Berlin Pro had fallen back to fourth place behind the Tasc R30, Mephisto Genius 68030 and Mephisto Risc 2.
In 1996 the Berlin Pro received a boost with Richard Lang’s London program upgrade. This added a further 35 or so Elo points. The London ROM is an easy replacement for the original program chip (see photo to the left). However even with the upgrade the Berlin Pro London now stands fifth on Selective Search’s final All-Time list (2013) with a rating of 2266, behind two Tasc R30 versions and two Mephisto’s running the same London program on faster 68030 processors.
It’s performance in Strong Group One was a little below par, but 18 games is really an insufficient test for accurately rating chess strength. There was a surprising loss to Renaissance Sparc 0.5/2 and the loss with white illustrates some weaknesses of what is otherwise a very powerful chess computer.