Installing FTDI and CH347 drivers on the second PC
Which two drivers the second PC needs, which card port each belongs to, and how to fix "unable to connect to USB/FT601" without reinstalling Windows.
Short answer
On the second PC, install the FTDI D3XX driver for the FT601 data bridge before any reader software, and the CH347 driver for flashing. Plug the cable into the card's data port, then confirm the device appears in Device Manager. "Unable to connect to USB/FT601" almost always means the wrong port, a charge-only cable or a missing FTDI driver.
On this page6
Which driver goes with which port?
Confusing the two ports is the most common reason a first build reports a dead card, so note which is which before you connect anything.
| Bridge | Driver | Port on the card | Used for |
|---|---|---|---|
| FT601 (FTDI) | FTDI D3XX | Data port | Everything after the flash: reading memory |
| CH347 (WCH) | CH347 / WCH driver | Flashing port | Pushing firmware onto the FPGA, reading the DNA ID |
Both drivers can be installed at the same time without conflict, so only the cable position changes between tasks.
How to install the FTDI data driver
Install this driver on the SECOND PC, because the game PC needs no driver at all and sees the card as an anonymous PCIe device.
- Boot the second PC with the card powered on and connected through its data port
- Install the FTDI D3XX driver package supplied with your order
- Open Device Manager and expand the USB and Universal Serial Bus controllers trees
- Confirm that a new FTDI device appears without a warning triangle
- If it shows as an unknown device, right-click it, choose Update driver and point it at the D3XX folder manually
- Reboot the second PC once after the driver installs
What driver errors mean and how to fix them
Work down the list, because each fix is cheaper than the one below it, and do not start by reinstalling Windows.
| Symptom | Likely cause | Fix |
|---|---|---|
| Unable to connect to USB / FT601 | Wrong port, a charge-only cable, or a missing FTDI driver | Move the cable to the data port and swap to a known data-rated USB 3 cable, then install the FTDI D3XX driver and reboot |
| Device appears then vanishes mid-read | A marginal USB link through a front-panel header, hub, dock or long cheap cable | Connect directly to a rear USB 3 port with a short, good-quality cable and remove every hub and extension from the path |
| Unknown device with a yellow triangle | Windows bound a generic driver to the device first | Uninstall the device with the option to remove its driver ticked, then unplug, reboot, install D3XX and plug the cable back in |
| CH347 tool sees nothing while the reader works | The cable is in the data port, but flashing needs the other socket | Move the cable to the flashing port and leave both drivers installed |
| Driver installs, device present, reader still fails | The card is enumerated, but either the game PC never initialised it or the problem is in the firmware layer | Cold-boot the game PC (full shutdown, wait ten seconds, power on), then re-check the BIOS virtualisation settings |
Info
Why doesn't the game PC need a driver?
The game PC's only job is to power the card and let its BIOS enumerate it as a PCIe device. Whatever identity the firmware claims, Windows on that side either loads a stock inbox driver or nothing at all. If someone tells you to install cheat drivers on the gaming machine for a DMA build, that goes against the reason you bought DMA.
Common questions about DMA drivers
Do I need to disable driver signature enforcement?
Not for the FTDI or CH347 drivers, because both are signed vendor drivers. If anything asks you to disable signature enforcement to install a DMA driver, check it carefully before you continue.
Can I use the second PC for anything else?
Yes, but keep its USB path clean, because a machine with fifteen USB devices on shared controllers will have intermittent read dropouts.
Will a USB 2 port work?
It may enumerate but will badly limit throughput, so use USB 3; the difference in read rate is very noticeable.
Does the FTDI driver version matter?
Use the version shipped with your order, because pairing a newer D3XX with an older reader build is a known source of odd, hard-to-reproduce failures.
Sources
The two-driver split and the error table are our own work: each row is a symptom we see on second PCs, paired with the fix that works.
- 01Hackaday, "Watch That Windows Update: FTDI Drivers Are Killing Fake Chips" (2014)
the FTDI driver update that disabled counterfeit FT232 chips, the precedent for pinning the driver version instead of chasing the newest
hackaday.com
Read next
Still stuck? Open a ticket on Discord
All guides