Thinkpads Forum

I have a T400 with a dock. Which dock it is precisely, I'll have to look up, but it has VGA and DVI connectors, but alas no sound jack. Video is switchable ATI Radeon HD3400.

I'd like to use it with two external monitors, and have no need to use the internal display. I've seen a youtube video using 2 monitors AND the internal display on Windows 7 using a combination of video drivers, but the comments seem to report that it's impossible with Win10 because of driver issues.

ATI doesn't provide its own driver for the HD3400 on Windows 10, but there is one included in Win10.

If you have this working, I'd appreciate some tips.

Chris

As you say the ATI HD3400 is not supported by Windows 10 end of story.
Your best option if you want to use Windows 10 is to use the Intel graphics and set that in the bios. I am not sure if that would support two external monitors though.
I would recommend going back to Windows 7 which works well with the T400 and the HD3400 GPU.

I'm surprised that AMD doesn't support the HD3400 via the Catalyst Legacy drivers.

Well it seems the Win 8 driver may work, but that it's supported via Windows Update.

Link:

http://support.amd.com/en-us/kb-article ... eries.aspx

Since Windows 10 uses the same basic driver interface as Vista, 7, 8, and 8.1.

I would suggest testing the Win 8 drivers, and if that fails, look into a HD5400 which the dock should support, there is current driver support, and it's a currently sold product type.