Thanks, the diagnostics gave the memory a clean bill of health, but before running the Windows diagnostic, I ran Memtest86, and after noticing that it appeared to be configured to only test a portion of the memory by default, I reconfigured it to test all. The strange thing was that it immediately spit out 10 errors, and it appeared that the test stopped. When I ran it again, also set to test all, it found no errors. This kind of left me hanging, thus the Windows test.
Since the Windows test won't run beyond 2 passes, I'm wondering just how thorough it really is? I know that memory defects sometimes takes many passes to find.