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RayeR(R)

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CZ,
06.10.2007, 23:36
 

Refresh rate control on new nVidia VGA is messed up,anyidea? (Miscellaneous)

I'm nVidia user for a long time because they provide VGA with VESA VBE 3.0 which include standard for setting up a refresh rate via CRTC vhen calling videomode bios init routine. This allows me to use Vbehz or Unirefresh TSR to see all programs in nice 85Hz.

It worked nice for nV from TNT to GeForce 4 I had tested but for newer 5xxx/6xxx/7xxx/8xxx models it doesn't longer work (60Hz only). But nvidia still claims VBE 3.0 - this violate the standard, it's effectively 2.0 now.
Someone guessed that nvidia disabled it to prevent angry stupid LCD users questions when they set more Hz to their poor LCDs.

Any idea how to set higher rates?
Maybe there are 2 ways
1) analyze nvidia bios if there's some disabled code and do some modding.
2) write own refresh control tool -
I think it is possible because windows drivers already can set it. And even Scitech SNAP SDK VBE test program using nucleus nvidia driver also can set it under pure DOS. But it's very hard to start write something because I cannot find any HW docs for nvidia chips :( I tried contact nV and Scitech but no reply.

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DOS gives me freedom to unlimited HW access.

Laaca(R)

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Czech republic,
07.10.2007, 15:39

@ RayeR

Refresh rate control on new nVidia VGA is messed up,anyidea?

Does it fail only under Windows or in pure DOS too?
I have a GeForce 4 and user refresh rate setting works only in pure DOS, under Windows everything looks OK but in fact the refresh frequency doesn't change. (what is interresting - if VbeHz in autoexec.bat (before windows start) it still works properly, if after - no effect)

And second question: fails only VbeHz and Unirefresh or VESA 3.0 programs with refresh control too? (If you don't have such application, test it with any program from my Wokna32 package - they all try to set the highest possible refresh rate)

Laaca(R)

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Czech republic,
07.10.2007, 15:51

@ RayeR

Refresh rate control on new nVidia VGA is messed up,anyidea?

In present the best source about programming the graphics cards are the sources of OpenBEOS (aka Haiku). They are smaller and simplier than these from Linux:
http://svn.berlios.de/viewcvs/haiku/haiku/trunk/src/add-ons/accelerants/

RayeR(R)

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CZ,
08.10.2007, 02:32

@ Laaca

Refresh rate control on new nVidia VGA is messed up,anyidea?

> Does it fail only under Windows or in pure DOS too?

Under pure dos, I don't care much about under win but it doesn't work too.

> I have a GeForce 4 and user refresh rate setting works only in pure DOS,

Yes I had GF4MX440 before and it worked fine. As I wrote it's issue of GF5xxx and newer.

> And second question: fails only VbeHz and Unirefresh or VESA 3.0 programs
> with refresh control too? (If you don't have such application, test it
> with any program from my Wokna32 package - they all try to set the highest

I tried many programs but all rely on VESA 3.0 standard of setting CRTC by calculated GTF. Simply nVidiots screwed it up in BIOS so ANY VESA program will not work. This must be enforced via setting some vendor specific registers in nVchip (far beyond VESA standrard) which are not probably documented.

BTW I read on some forum that ATI VGA BIOS can be modified by bios editor to override default refresh rates. ATI, as I know, provide only VESA 2.0 but now with this feature it is better than nVidia VESA 3.0 (but I don't know what else bugs may ATI VESA BIOS have).

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DOS gives me freedom to unlimited HW access.

RayeR(R)

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CZ,
08.10.2007, 02:59

@ Laaca

Refresh rate control on new nVidia VGA is messed up,anyidea?

> In present the best source about programming the graphics cards are the
> sources of OpenBEOS (aka Haiku). They are smaller and simplier than these
> from Linux:
> http://svn.berlios.de/viewcvs/haiku/haiku/trunk/src/add-ons/accelerants/

Thanks, at 1st look it seems this drivers include rsfh rate ctl, yeah simpler but still 600kB of sources to analyze, when will be time...

p.s. it covers up to NV30 I don't know anything about nvchips compatability, maybe for G73 it is totally different...

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DOS gives me freedom to unlimited HW access.

DOS386(R)

16.10.2007, 02:01

@ RayeR

Refresh rate control on new nVidia VGA is messed up,anyidea?

> nVidia user for a long time because they provide VGA with VESA VBE 3.0
> which include standard for setting up a refresh rate

> It worked nice for nV from TNT to GeForce 4 I had tested but for newer
> 5xxx/6xxx/7xxx/8xxx models it doesn't longer work (60Hz only). But nvidia
> still claims VBE 3.0 - this violate the standard, it's effectively 2.0 now.

It's a subset of 3.0 only :-(

> I think it is possible because windows drivers already can

Very true. Everything is possible in DOS - just a question of "cost" :-|

It's a sad truth that VESA tends to be buggy, ATI is worst (?), NVIDIA maybe slightly better ... but VESA is 15 years old and has very low priority for card developers ... they NEVER document the presence of VGA or VESA ... OTOH it usually minimally works :-|

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This is a LOGITECH mouse driver, but some software expect here
the following string:*** This is Copyright 1983 Microsoft ***

RayeR(R)

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CZ,
17.10.2007, 11:38

@ DOS386

Refresh rate control on new nVidia VGA is messed up,anyidea?

> Very true. Everything is possible in DOS - just a question of "cost" :-|

Yes. With clear documantation from nvidia directly for specified chip it would be much easier. I'm not angry they don't provide code for something but documentation is needed to code it myself...

> It's a sad truth that VESA tends to be buggy, ATI is worst (?), NVIDIA

Do you (anybody else here) have any experiences with modern ATI VESA BIOS? I was nvidia fan and had only nv cards for long years. But as I know ATI would be better because it allows you to hardwire your own refresh rates via bios editor even it had only VBE 2.0 so this is an advantage over nv.

> maybe slightly better ... but VESA is 15 years old and has very low

I think VE 3.0 was "only" ~10 years old :) But I'm afraid that VESA nad also VGA compatability will disappear and will be replaced by some EFI. Then it will be end of DOS era on real HW, only emu will be possible.

Another thing how nvidiots sucks my blood (i wrote here to upper thread):
I found another source of problems with running VGA/VESA DOS programs fullscreeen under NT/2K/XP NTVDM - New nVidia BIOSes are missing some functions (VBE-PM?) which cause that any VGA/VESA program I run displays only black screen ad hangs. It happened on 7600GS after VGA BIOS update. The new version is about 5kB smaller so it's clear that something is missing. Solution is downgrade back or use http://www.volny.cz/martin.sulak/videoprt.zip hook driver which gives back some missing functionality. After I installed it I can run VGA/VESA DOS progams as before under XP.

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DOS gives me freedom to unlimited HW access.

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