I had an occasion to use Windows XP on my computer so i decided to make a FaceToFace comparison.

Testing system:
Celeron, Tualatin 1,12 Ghz
1,5 GB ram
Ati Radeon 9800Pro
ATA100 disks, Fat32

Functionality of following items has been examined:

Soundcard: FM801 with Radio tuner
Drivers: FM801 - 2.01, Terratec i512 - 2.00g (both WDM)
Application: PCIRadio (Radioaktiv 4.0)

TvTuner: PV951
Driver: Ivan Uskov's Tweaked drivers (WDM)
Application: ATV2000 by mike crash

Video Player: Windows media player Classic by Gabest (MPC)

Ultima Online

The Elder Scrolls: Oblivion



Windows 98SE + SP2 + KUP, DX9.0c
Boot time: 45s-1minute

Sound Card
Sound driver FM801 2.01 was causing following issues:
Slowing down Internet Explorer, sound corruption while playing, loud beeping while Ultima Online was running

Sound driver i512:
Silent beeping while Ultima Online was running

PciRadio - Error message that Radio tuner is not available - common bug at WDM version of drivers for this card, with both drivers
Radio sucesfully started despite error.

TV Card:
No issuses caused by driver.

Application is giving error message "Video frame grabber cannot be found", during startup is system choppy.

Available video renderers:
Video Renderer (default)
Video Mixing Renderer 9

Video player
No known issues

Available video renderers:
Video Renderer (default)
Video Mixing Renderer 9

Ultima Online
Issues caused by sound card already mentioned

Oblivion:
Long start time, sometimes missing audio - mostly dialogs

Windows XP, home edition, SP2, DX9.0c
Boot time: 1-2 minutes

Sound Card
Sound driver FM801 2.01 was causing following issues:
Control panel of sound provided by forte media was crashing constantly

Sound driver i512:
Silent beeping while Ultima Online was running - same bug as in w98

PciRadio - Error message that Radio tuner is not available - common bug at WDM version of drivers for this card, with both drivers.
Radio didnt start

TV Card:
No issuses caused by driver.

Application is giving error message "Video frame grabber cannot be found"(same as w98), system was not affected during start.

Available video renderers:
Video Renderer (default)
Video Mixing Renderer 7
Video Mixing Renderer 9

Video player
No known issues

Available video renderers:
Video Renderer (default)
Video Mixing Renderer 7
Video Mixing Renderer 9

Ultima Online
Issues caused by sound card already mentioned

Oblivion:
No visible bugs.

Conclusion:
All that worked with Win XP also worked with upgraded Win98SE. There is but one very strange difference and it is presence of DX 7 video renderers in WinXP and absence of them in Windows 98 which have been upgraded by DirectX 9.0c redist pack from oblivon package.

There is high possibility that ATV2000 and Oblivion (game designed for winxp) are trying to load dx7 interfaces which are natively present in windows XP, and this is causing all issues with sound and video. For example if are DX sound acceleration disabled in win98 all issues in Oblivion vanish (at cost of performance)

Presence of DX7 interface can be easily detected by WMPC by gabest, in Options, Output , and in "Direct Show Video" table.


Why is DX7 interface present in WinXP, and absent in Win98SE even updated with DX9 package?

hard to say, but i am sure that presence of both of them can give better compability and reliability.

Is there any way how to install them both at Windows98?

The directx 7 interface is present in Windows 98...
Or at least it is supposed to be. I play several games in windows 98 that use directx7 with no problems.

directx 6.1 is included with win98 and directx 7.0 is included with windows me

what i know is that DX9 can work with all aplications which were designed for previous versions. but for me is quite strange that in win98 is present only one Video Mixing Renderer from DX9, and previous renderer v7 is absenting...

I try to uninstall DX9, install DX 7 and then dx 9. shall see...

My 2 ¢

DX 9.0c [same as all other 8.xx + 9.xx versions] should install backward compatible DX7 APIs.
Any app/game/tool/driver using older DX7 interface should work ok. If it doesn't, then it is poor programming.

HTH

I suspect that some applications created under winXP are addressing "Video Mixing Renderer 7" instead of adressing default "Video Renderer", althought it seems that they are completely identical. It seems that in windowsXP are two separate threads of registries with different name leading to one VMR7 interface. application which is compatible in winXP it can cause trouble in win98 because of poor programming.

I try to extract them, rewrite and add to Windows 98 registry entries.

Edit:
Yes my suspicios was true. Video Mixing Renderer 7 = Video Renderer (Default). Both are same in Windows 98 and XP but in XP it can be addressed by two methods. There is no benefit when using VMR7 instead of Default renderer, but a little bit important is that it makes difference between ms OSs and lowers compatibility...

So which files from DX 9.0c have you hex-edited and corrected to work properly with Win98/98 SE/ME?
Can you post them here or email them to me [ http://www.mdgx.com/form.htm ] so I can create an iexpress installer and post it/them at my site?

Thanks.