mp4 files suddently stopped working with IGPU but work fine with GPU

[kiwisam]

Hi,
Just upgraded my PC and have a ASUS H87 Mobo with Intel HD4600 IGPU as well as my original (and old) ATI RADEON PIC-e 4800 series GPU from about 6 years ago. Set up the system over the weekend with IGPU as my primary adaptor (because I needed the 3D input to the projector) and set up GPU as secondary to a second (extended) display.

Everything worked well last night but when I booted up today I could no longer play any mp4 or mkv files with either WMP12 or Nero Platinum14 MediaHome (both working last night but now the file either won't open (MediaHome) or just plays audio (WMP)) - there are no error messages returned. There are other media players that I have (3D Video Player and an old version of Nero Showtime) that played all of the files fine.

Additionally, all of the players (Including WMP and MediaHome) play avi files no problem - unsurprisingly, changing the fine name from mp4 to avi did not solve the problem.

When I disable the IGPU and use the discrete GPU all of media players work fine still (including WMP and Mediahome). This suggests to me that the issue is something to do with the Intel HD4600 drivers (rather than a Win7 codecs issue) but can't see why they were fine yesterday but not today - after the issues first appeared I checked on line and found a slightly newer driver which I downloaded but this made no difference. I have also tried using system restore but that left me with more problems than when I started so gave up on that approach.

Between successful use last night and rebooting today I did install a number of the drivers/utilities from the ASUS support disc that came with the Mobo and uninstalled a number of older utilities that were no longer supported (i.e. earlier versions of AI Suite etc). I don't believe any of these drivers or utilities were display/IGPU related so I haven't gone through and uninstalled them all on the off chance but guess that is the next thing for me to look at......

I have emailed Intel but am not expecting much back from them - am sure they will tell me it is either a Win7 problem or an application problem.......

Any advice appreciated although I don't want to be told to install VLC etc - the fact is I like WMP and MediaHome and I they were working before they should work again!

Cheers,

Sam

 

[KingFatty]

Are you able to remove the discrete video card, to see if the problem resolves when running them using *only* the HD4600? I mean you would take the HD4800 out of the computer, physically.

 

[kiwisam]

Yes - removing the discrete GPU 'fixes' things and I realise that this is probably the first thing I should have done but I had just finished screwing the case back together and burying the HTPC into the entertainment cabinet so was trying to avoid that if I could!

Am updating all graphics drivers I can find for both the removed GPU and the IGPU and will see what happens when I put it back in (possibly not tonight).....

 

[kiwisam]

ok - so removed the RADEON HD4800 card and everything works fine.

Put it back in and everything goes belly up again. Also noticed that in addition to the issue with the media players other strange graphics things occurs e.g. trying to running Windows 7 Spider Solitaire gets an error message "no suitable graphics installed" and a few other programs open with 100% transparent windows i.e. I get the windows frame plus whatever program is running in the background rather than what is expected.

Removed HD4800 again and back to everything working straight away - will try installing GPU again but disabling it in device manager as despite disabling the installed card in BIOS it is still reported in device manager as installed and working....