I recently upgraded my memory to 512mb of PC800 ECC RDRAM (2x256mb). My computer recognized the change in system memory, and now lists 512.0mb RAM in "system properties" instead of 128mb. However, my system crashes and memory-related error messages have increased. Sometimes after I start my computer with a minimal number of start-up programs and attempt to open my first program, I get an insufficient memory error message! This never happened before.
Although I no longer use the Norton Anti-Virus program, I still have Norton System Works (2001) installed and I ran their "Norton Diagnostics" program to test the new memory. The first test or pattern which this program runs is described as: "Testing memory using pattern with all bits cleared..." Each time I run this program, after about one second it indicates "Error detected at address xxxxx" and "Test: Failed." Every time I redo the test it indicates an error at the same address. After I reboot, however, the address of the error changes (and remains consistent until I reboot again).
In an attempt to confirm that my new memory was defective, I researched other memory testing programs and discovered Microsoft's "Windows memory diagnostic" program, which runs a "standard" set of 6 memory tests and an "extended" set of 11 memory tests (from a bootable floppy disk). My new memory passed the standard set of 6 tests so I switched to the "extended" test set and let it run overnight. In the morning, I discovered that my new memory passed all the tests with no errors.
Thus, it seems to me that either the "Norton Diagnostic" program is defective or my new RDRAM is defective. Which is more likely? Might the Norton Diagnostic program use a test (i.e., using a pattern with all bits cleared) which can detect errors in ECC RDRAM that the Microsoft diagnostic program cannot detect? Is there another explanation? I would appreciate any helpful suggestions!