Radeon HD 4670 Windows 10 Driver problem

[skarux]

Good morning everyone,
I have just bootcamped my iMac 21.5" Late 2009 with Windows 10 but I am having problems with Video drivers: the one included in the bootcamp pack that I used till Windows 8.1 (BootCamp5.1.5621) does not work anymore (even trying to manually install the .inf file it says that's not compatible with this OS) and the the one downloaded from AMD support site has maximum resolution of 1440x-----, but the worst thing is that the screen appears like divided in 4 squares with completely distorced colors with the same image repeated 4 times (I've got the same issue with the driver downloaded from windows update and booting from a pen drive with kubuntu).
I thought about installing first Win 8.1, fixing the driver and then updating to Win 10, but I'm afraid that Win 10 would remove the incompatible driver.
Anybody else had the same issue?

Thanks

 

[chscag]

Keep in mind that your 21.5" iMac does not use the normal Windows desktop drivers, instead it uses the mobile driver set. Make sure you download the mobile AMD driver set and try again. Otherwise you'll need to wait until Apple updates its version of Boot Camp for Windows 10.

 

[skarux]

I have downlaoded the drivers explicitly made by Ati for the iMac (not desktop nor mobile); I am afraid I will never get anything by the next bootcamp update since my iMac is considered a deprecated system

 

[chscag]

I have downlaoded the drivers explicitly made by Ati for the iMac (not desktop nor mobile); I am afraid I will never get anything by the next bootcamp update since my iMac is considered a deprecated system

That's a valid point. Your iMac may not be capable of running Windows 10 if Apple does not update Boot Camp for your machine. In that case, I would revert to running Windows 7 which is a rock solid version of Windows, or stick with 8.1. I'm not especially impressed with Windows 10 but that's just my personal opinion.

I thought about installing first Win 8.1, fixing the driver and then updating to Win 10, but I'm afraid that Win 10 would remove the incompatible driver.
Anybody else had the same issue?

I would give this a try as a last resort. Just make sure that you backup your Windows installation first. We recommend using WinClone to do the backup image.

 

[skarux]

Your iMac may not be capable of running Windows 10 if Apple does not update Boot Camp for your machine

Apple does not even support Windows 8, I use a small trick to install bootcamp.

In that case, I would revert to running Windows 7 which is a rock solid version of Windows

Windows 7 mainstream support has already ended, moreover newer versions of Visual Studio support it just partialy; it is not a valid choice.

[SOLUTION]
At the end I have succeded making Windows 10 video drivers working: I have first installed Windows 7, then bootcamp and finally I have updated to Windows 10. During Windows 10 installation the resolution has been reverted to the minimum one (something like 1024x768, I'm not sure; anyway installing Windows 10 directly the generic Microsoft video driver was able to bring to 1920x1080) and then Windows succesfully downloaded and installed the needed driver from Windows Updates.
Since the driver is the same I think that probably there was some kind of conflict with other drivers, probably the Win 10 display one.
The only big difference (but it should be completely uncorrelated) is that before I was using a disk partitioned using GPT and now an hybrid MBR (btw Win 8 and 10 can not be installed directly on an hybrid MBR disk because they are able to detect GPT and so they want a GUID partition).

Anyway thanks for the attention.

 

[chscag]

Glad to hear you got it working. One thing I forgot to mention earlier is that Windows 8.1 and Windows 10 both are EFI aware and will pick up on an EFI boot sector that a modern Mac uses. Several PC manufacturers are likewise going to EFI rather than continue to use a BIOS.