Windows Memory Diagnostic Mdsched Command |verified| < UHD 2027 >

A single pass with no errors does not guarantee 100% reliability. Some intermittent faults require thermal cycling or extended looping ( /l ). 6. Limitations and Comparison | Aspect | Windows Memory Diagnostic | MemTest86 (Professional) | |--------|---------------------------|---------------------------| | Test algorithms | 7 basic patterns | 13+ advanced (including row hammer) | | Error reporting | Event log only | On-screen with address/bit mapping | | ECC support | Reports corrected errors | Reports corrected + location | | USB bootable | No (requires Windows bootloader) | Yes | | Loop time | Unlimited ( /l ) | Configurable | | CPU cache control | Limited | Full enable/disable |

| Code | Meaning | Recommended Action | |------|---------|---------------------| | No errors | No faults detected | Consider other components (CPU, storage, drivers) | | Single-bit error | Correctable ECC error (server RAM) | Monitor; may be cosmic radiation | | Multi-bit error | Uncorrectable fault | Replace the specific DIMM | | Address error | Faulty memory controller or motherboard slot | Test individual DIMMs in different slots | windows memory diagnostic mdsched command

| Test Phase | Algorithm | Detection Capability | |------------|-----------|----------------------| | | Moving Inversions (8-bit pattern) | Simple stuck-at faults | | INVC | Inverse word write/read | Data line shorts | | LRAND | LFSR-based random pattern | Timing-sensitive errors | | Stride6 | 64-bit block writes with varying strides | Address line coupling | | WCHK3 | Write checkerboard pattern | Adjacent cell interference | | ERAND | Extended random pattern | Complex intermittent faults | | Stride38 | Aggressive cache-refreshing pattern | Row hammer vulnerabilities | A single pass with no errors does not

| Parameter | Function | |-----------|----------| | (no args) | Opens the GUI dialog with two options: Restart now and check, or Schedule on next boot. | | /l | Runs the diagnostic in loop mode (continuous testing until manually stopped). | | /s | Shuts down the system immediately before starting the diagnostic. | | /r | Restarts the system immediately before starting the diagnostic. | | /c | Runs the diagnostic in extended cache mode (more thorough, longer duration). | | /? | Displays help. | Limitations and Comparison | Aspect | Windows Memory

mdsched.exe [options]