WK2 Server becomes unresponsive

I have a Dell PowerEdge 800 running Windows 2000 Server SP4, 1GB Ram, Symantec Endpoint Protection 11.0.5 (Latest Version). I have been running into instances where when I come in on some mornings the server is unresponsive or hung. You can't ping it or remote to it. The console is black but the lights are still on the box. This doesn't happen everyday. Sometimes I can go several weeks until it happens again. I have checked for memory leaks in programs, I haven't found any. I found a Hotfix from Microsoft for unresponsive WK2 systems reading through the posts here. I applied the patch on Thursday. I came in on Monday and I had a BSOD waiting for me. This is the error code: 0x0000007 (0xc0000185, 0xc0000185, 0x00000000, 0x000D2000) Kernel_Stack_Inpage_Error) So I looked up some of the stop codes and some point to the Ram and some to the harddrives. System is in a RAID 5 with 4 drives. I ran chkdsk /r on all the partitions and they come up clean. I installed RUBotted on the system to see if maybe the system was being crashed remotely nothing came up. I come in this morning and the system is unresponsive again. I got Dell on the phone and they had me update the SCSI Drives firmware, BMC and SCSI controller firmware. I am currently running a memory test on the system to check the RAM. Also yesterday I reseated the memory chips. Now, I know I should get this system off Windows 2000 Server but money is a factor here. Has anyone ran into this problem before. I am scheduled to go on vacation at the end of the week and I need to get this resolved. Help!!