Infoworld is reporting that there is a very significant memory leak in Windows 7 involving the chkdsk.exe utility which appears when
you attempt to run the program against a secondary (that is, not the boot partition) hard disk using the "/r" (read and verify all file data) parameter. The problem affects both 32- and 64-bit versions of Windows 7 and is classified as a "showstopper" in that it can cause the OS to crash (Blue Screen of Death) as it runs out of physical memory.
Randall Kennedy tested the bug against a variety of different builds of the RTM Windows 7. The bug appeared in VMs, 32-bit Netbooks and 64-bit laptops. The bug also appears in Windows Explorer when you run the integrated disk check utility