DMA troubleshooting,
step by step.

What it usually means

The card or its connection did not recover cleanly after a fast restart, sleep, or a previous session. The test cannot initialize the memory manager until the hardware link is responsive.

Work through these checks

1. Close the test on the secondary PC.
2. Fully shut down the main PC. Wait at least 10 seconds before powering it back on.
3. Reseat the DMA data cable, let both PCs finish starting, and rerun the full test.
4. If it returns after sleep, use a full shutdown before testing again.

What it usually means

Windows cannot see the FT601 interface. The usual causes are a missing D3XX driver, a charge-only cable, the wrong card port, or an unreliable USB connection.

Work through these checks

1. Confirm the cable is connected to the card’s data port rather than a power-only or JTAG port.
2. Connect directly to a USB 3 port on the secondary PC; temporarily remove hubs and adapters.
3. Check Device Manager for the FTDI FT601 device.
4. If it is absent or has a warning icon, install the current FTDI D3XX driver ↗, then reconnect the card.
5. Try a known data-rated USB 3 cable.

What it usually means

The device was found, but the read path was not stable enough to collect the main PC’s physical memory layout. This points first to connection quality.

Work through these checks

1. Perform a full shutdown of the main PC and restart it.
2. Reconnect both ends of the USB cable and avoid front-panel ports or hubs during diagnosis.
3. Try another USB 3 port, followed by another known-good data cable.
4. Inspect the card and bracket for movement that prevents the connector from seating fully.

What it usually means

The tool cannot find or retrieve the symbol information it needs. An incomplete extraction, a missing DLL, or blocked network access is often responsible.

Work through these checks

1. Extract the entire ZIP instead of running the executable from inside the archive.
2. Keep lone-dma-test.exe, symsrv.dll, and dbghelp.dll together with the other included files.
3. Confirm the secondary PC has internet access and that security software is not silently quarantining an included file.
4. Use only symbol files supplied by the tool’s repository or your trusted hardware provider.

What it usually means

The stack selected a more conservative transfer method. The test may still run, but throughput can be lower because of the USB link, PCIe conditions, or firmware behavior.

Work through these checks

1. Reseat the data cable and test another direct USB 3 port.
2. Repeat the test with a different, short USB 3 data cable.
3. Power down both systems before reseating the card in its PCIe slot.
4. Confirm your firmware is intended for the exact card model. Do not flash an unknown image simply to chase a higher score.

What it usually means

The hardware link may exist, but the tool cannot identify a usable Windows memory translation base. Connection instability, an unsupported state, or setup-specific firmware and BIOS requirements can cause it.

Work through these checks

1. Cold-boot the main PC and rerun the test before changing system settings.
2. Repeat the cable and USB-port checks from the connection section.
3. Confirm the tool, firmware, and target Windows version are supported by your hardware provider.
4. Review your card’s documented BIOS requirements. Change virtualization or security settings only when the vendor documentation specifically requires it and you understand the impact.

What it usually means

The connection works, but it is not moving data consistently. Cable quality, USB controller choice, power management, PCIe seating, and firmware can all affect the result.

Some community guides use roughly 4,000 memory reads/sec or 125 MB/s as low-result indicators. Treat these as diagnostic cues; your card model and software requirements determine the meaningful target.

Work through these checks

1. Use a short, data-rated USB 3 cable connected directly to the secondary PC.
2. Try rear motherboard USB ports on different controllers and record each result.
3. Use an appropriate performance-focused Windows power mode while testing.
4. With both PCs powered off, reseat the DMA card and confirm its bracket is not pulling the USB connector sideways.
5. Run an extended five-minute test. Watch for dropouts and large swings, not only the peak number.

What it usually means

The executable was separated from its libraries, Windows blocked a downloaded file, or the expected Visual C++ runtime is unavailable.

Work through these checks

1. Extract every file from the ZIP into one folder on the secondary PC.
2. Confirm the included DLLs remain beside lone-dma-test.exe.
3. Open the included README and compare the folder contents with the repository.
4. If the error references a Visual C++ runtime, install Microsoft’s Visual C++ 2015–2022 Redistributable (x64) ↗.