diff --git a/build/sims/config.202 b/build/sims/config.202
index 5ead7339..05111f06 100644
--- a/build/sims/config.202
+++ b/build/sims/config.202
@@ -254,7 +254,7 @@ DEFOPT NSTTYS==8	;# STY'S (PSEUDO-TTY'S)
 DEFOPT TEN11P==1	;Rubin 10-11 interface
 IFDEF TEN11P,IFN TEN11P,DEFSYM T11CPA==3776000	;ADRS OF TEN-11 CONTROL PAGE
 
-DEFOPT TSYSM==512.	;TOTAL PDP10 1K MEM BLOCKS
+DEFOPT TSYSM==768.	;TOTAL PDP10 1K MEM BLOCKS
 DEFOPT NMMP==4		;# EXEC PAGES FOR MMP TABLE (# VIR PGS/512.)
 
 DEFSYM PMRCM==1777	;10 BIT REAL CORE ADR