The subject says it all. My system was happily running BOINC and SETI@HOME using 8 cores and my GPU. I upgraded to windows 10 and the GPU crunching stopped. I uninstalled and reinstalled and deleted data file and made sure my video driver is current. However, it seems I can no longer get any GPU action.

I have seen a couple of odd things though:
BOINC Manager says I'm running SETI@home v8 8.00 with an executable of setiathome_8.00_windows_intelx86.exe. Isn't the current version 8.20?

The event log appears to recognize the presence of my GPU:
12/23/2016 4:10:37 AM | | CAL: ATI GPU 0: ATI Radeon HD 4600 series (R730) (CAL version 1.4.1734, 1024MB, 992MB available, 704 GFLOPS peak)

And it even tries to get GPU tasks:
12/23/2016 4:18:24 AM | SETI@home | Requesting new tasks for CPU and AMD/ATI GPU

After 8 processes start - one for each core and HT I see:
12/23/2016 4:50:27 AM | SETI@home | This computer has reached a limit on tasks in progress

I've never seen a setting for the maximum number of tasks running. But I still don't see a process running for my GPU.

Any suggestions?

Thank you.

---

.. and made sure my video driver is current..

That's most probably the problem. AMD stopped support for OpenCL for the older HD4xx0 GPUs back at driver 12.10, so the only thing you have is CAL support and there is no application at Seti anymore that uses only CAL. All applications for the AMD GPUs are OpenCL.

So you'll need to install an older driver, something like Catalyst 12.1 WHQL. You'll need to completely uninstall the driver in Windows before that, then on the reboot cancel any driver Windows tries to auto-install and instead install the driver given.

Now, I don't know if Windows 10 will support this driver and I surely don't know if Windows 10 won't immediately try to install 'a better, newer' driver. But know that the better newer driver lacks the necessary component, OpenCL. So tell Windows to back off on auto-updating your hardware drivers.
I also don't know if Windows 10 will actually be able to use the GPU, as according to this page from AMD the driver you use now is the driver installed in Windows 10 for use for the GPU. However, as noted, it doesn't have OpenCL and therefore the GPU can only be used as a videocard, not for calculations.

If you do manage to get it to work though, last bit of advice is to free at least one CPU core so it can be used by the GPU.

The following Discrete AMD Radeon™ Graphics products support up to WDDM 1.1 and DirectX® 10.1:

ATI Radeonâ„¢ HD 4000 Series /ATI Mobility Radeonâ„¢ HD 4000 Series Graphics
ATI Radeonâ„¢ HD 3000 Series /ATI Mobility Radeonâ„¢ HD 3000 Series Graphics
ATI Radeonâ„¢ HD 2000 Series /ATI Mobility Radeonâ„¢ HD 2000 Series Graphics

These graphics products must be installed using display driver version: 8.970.100.9001. This driver is provided as a courtesy and only available via Windows Update. Please enable Windows Update and allow it to detect and install the appropriate driver.

---

does this include open cl support or is that separate

Those older drivers include OpenCL for the ATI HD4xx0 GPUs..

---