J20,21 Outline for 20 pin header?  J4-19 72 pin SIMM

U1,2 Corollary DPX  U3 Corollary CMC

U1,2 Corollary DPX 94C101B 
U3 Corollary CMC 94C101A 

Error code EP:1043 
    A Server 720 halts with error code EP:1043 (EP:104X). This code can not be found in the Server 720 HMM (Hardware Maintenance Manual) supplement, S30H-2352-00, dated October 1995.  

Fix  
   Error code EP:1043 is not listed in the HMM. This error code reflects a memory adapter failure. First reseat the memory adapter, as it could be loose or not fully seated in the connector on the system board. If the error persists, the memory adapter is the most likey failing FRU. (FRU P/N71G0696). 

Possible Memory Configurations

MBs	Mem Card 1  Bank A	Mem Card 1 Bank B	Mem Card 2 Bank A	Mem Card 2  Bank B
64MB	8 x 8MB	empty	empty	empty
128MB	8 x 8MB	8 x 8MB	empty	empty
128MB	8 x 16MB	empty	empty	empty
192MB	8 x 8MB	8 x 8MB	8 x 8MB	empty
256MB	8 x 8MB	8 x 8MB	8 x 8MB	8 x 8MB
256MB	8 x 16MB	8 x 16MB	empty	empty
256MB	8 x 32MB	empty	empty	empty
320MB	8 x 16MB	8 x 16MB	8 x 8MB	empty
384MB	8 x 16MB	8 x 16MB	8 x 8MB	8 x 8MB
384MB	8 x 16MB	8 x 16MB	8 x 16MB	empty
384MB	8 x 32MB	8 x 16MB	empty	empty
512MB	8 x 16MB	8 x 16MB	8 x 16MB	8 x 16MB
512MB	8 x 32MB	8 x 32MB	empty	empty
576MB	8 x 32MB	8 x 32MB	8 x 8MB	empty
640MB	8 x 32MB	8 x 32MB	8 x 8MB	8 x 8MB
640MB	8 x 32MB	8 x 32MB	8 x 16MB	empty
768MB	8 x 32MB	8 x 32MB	8 x 16MB	8 x 16MB
768MB	8 x 32MB	8 x 32MB	8 x 32MB	empty
896MB	8 x 32MB	8 x 32MB	8 x 32MB	8 x 16MB
1GB	8 x 32MB	8 x 32MB	8 x 32MB	8 x 32MB