Geforce gtx 750 ti drivers do not get installed - instead Win 8.1 Pro forces to use Microsoft driver

Hi,

Problem: although the latest NVidia driver version is downloaded and installed to Win 8.1 Pro
a) OS keeps Microsoft general drivers for Geforce-GTX 750 Ti
b) OS allows NVidia drivers for the second GPU card NVidia Quadro FX 1800

Goal: the latest NVidia driver for both GPU installed
a) MSI-GeForce-GTX-750-Ti in PCIex16_1 via HDMI cable
b) NVidia Quadro FX 1800 in PCIex16_2 via DisplayPort

Questions:

  1. how to get the latest NVidia driver for both GPUs ?
  2. can I delete MS driver without any risk ?
  3. can I delete MS Media Player - for some guys it has prevented NVIdia drivers ?
  4. is there any way to replace existing GPU drivers ?
  5. there seems to be conflict in information regarding what drivers the system uses, why :
    a) NVidia tool shows that everthing is ok and its drivers hae been installed ok, why ?
    b) MS OS shows that monitors are working ok with MS general graphics driver installec to 750 Ti
  6. is it possible to onnect 750Ti via HDMI cable and to get system to use NVidia drivers ?
  7. is there available any simple just install it tool ?
  8. Linux kernel went to “panic” with GTX-750-Ti driver and Win 8.1 Pro just ignores it, why ?

Tips - specially detailed step by step instructions how to get NVidia’s latest driver installed to both my GPU cards - more than welcome !

Mixing Quadro and GeForce boards is not considered as supported configuration, because their drivers do not expose the same OpenGL extensions, have different control panels, capabilities, and tools.
To make matters more difficult, your boards have GPUs with completely different chip architectures, three(!) generations apart.
Even if the same driver versions (where Quadro/Tesla and GeForce installers are actually different packages) work for each of them individually (did you try that?), that doesn’t mean they can handle arbitrary multi-GPU configurations like yours.