Linux + refresh rate + Quadro4 ... little help please :)

[Chem]

Hi guys,

far from a *nix guru here. I have a dual AMD Athlon 2100 workstation with 1 gig ram and a brand-spankin-new Quadro4 750 XGL installed under RedHat 8.

My problem is this: the system seems to only want to run at a max of 85 Hz refresh rate. We need higher for stereo viewing (the reason we got the quadro in the first place). I am using a fresh install of the new 43.xx drivers released yesterday. My XFree86Config file has been edited with the correct horiz/vert ranges for my monitor.

An excerpt from the XF86 boot log:

(II) NVIDIA(0): NVIDIA GPU detected as: Quadro4 750 XGL
(--) NVIDIA(0): VideoRAM: 131072 kBytes
(II) NVIDIA(0): Connected display device(s): CRT-1
(--) NVIDIA(0): Display device CRT-1: maximum pixel clock at 8 bpp: 350 MHz
(--) NVIDIA(0): Display device CRT-1: maximum pixel clock at 16 bpp: 350 MHz
(--) NVIDIA(0): Display device CRT-1: maximum pixel clock at 32 bpp: 350 MHz
(II) Loading sub module "ddc"
(II) LoadModule: "ddc"
(II) Loading /usr/X11R6/lib/modules/libddc.a
(II) Module ddc: vendor="The XFree86 Project"
compiled for 4.2.0, module version = 1.0.0
ABI class: XFree86 Video Driver, version 0.5
(II) NVIDIA(0): MyMonitor: Using hsync range of 30.00-140.00 kHz
(II) NVIDIA(0): MyMonitor: Using vrefresh range of 50.00-160.00 Hz
(II) NVIDIA(0): Clock range: 12.00 to 350.00 MHz
(II) NVIDIA(0): Not using default mode "1024x768" (bad mode clock/interlace/doublescan)
(II) NVIDIA(0): Not using default mode "512x384" (bad mode clock/interlace/doublescan)
(**) NVIDIA(0): Validated modes for display device CRT-1:
(**) NVIDIA(0): Default mode "1600x1200": 229.5 MHz, 106.2 kHz, 85.0 Hz
(**) NVIDIA(0): Default mode "1280x1024": 157.5 MHz, 91.1 kHz, 85.0 Hz
(**) NVIDIA(0): Default mode "1024x768": 94.5 MHz, 68.7 kHz, 85.0 Hz
(**) NVIDIA(0): Default mode "800x600": 56.3 MHz, 53.7 kHz, 85.1 Hz
(**) NVIDIA(0): Default mode "640x480": 74.2 MHz, 85.9 kHz, 85.1 Hz (D)

---

so my question is this: how can I get my system to use the fastest supported refresh rate for the monitor/ramdac combo at each resolution? We need at least 120 Hz @ 1280x1024, for example.

I searched google and a few faqs, found nothing useful.

thanks,

Brian

[Andy Mecham]

What monitor are you using?

--andy

[Chem]

NEC MultiSync FP2141 SB

from the manual:

Sync range..
horiz: 30-140 kHz
vert: 50-160 Hz

Resolutions supported: (not listing all here...)
800x600 @ 50 - 160 Hz
1024x768 @ 50-160 Hz
1280x1024 @ 50-127 Hz
1600x1200 @ 50-109 Hz

fyi, andy, I had found a web article off google that complained of the same problem (default of 85 Hz) under Mandrake 9 and RH 8.
http://cd-rw.org/articles/archive/mandrakeredhat.cfm

-Brian

[Andy Mecham]

You'll probably need to do one of the following:

1) write a custom modeline for the resolution/refresh you want. There are several tools on the web that can help you with this.

2) try using the UseEdidFreqs option in your XF86Config file.

Thanks!

--andy

[Chem]

yeah I was thinking I might end up at #1. put that in for my #1 request for the next linux driver release... having user-configurable or optimized-by-default refresh rates.

If you can do it in windows....

-Brian

[Chem]

ok, an update. I have things 'mostly' working:

I tried 3 different websites that feature XFree86 Modeline generators. None of them worked propely on my NEC 22" monitor and Quadro4. I'd either get an error relating to HSW/VSW or the image would just plain not be correct (spilling off screen, odd looking lines, shifted too far left, etc..)

I ended up starting x to its regular 85 Hz 1280x1024 setting and running xvidtune, then using the 'show' button of xvidtune to show the exact modeline details for the 85 Hz mode.

Then I simply added that line back in as a custom definition but with a bumped up pixel clock (ramdac) speed. voila, my display has the correct proportions and functions fine, BUT...

there's just a bit of fuzziness. a bit of blur in text. just enough such that it's annoying. yes, as described above, my monitor should be just fine @ 120 Hz. fiddling with the on-board monitor settings hasn't fixed it.

The modeline I'm currently using is:

Modeline "1280@" 223.00 1280 1344 1504 1728 1024 1025 1028 1072

any ideas would be appreciated!

-Brian

[Andy Mecham]

XFree86 4.3 includes gtf for determining modelines.

Running 'gtf 1280 1024 120' returns

# 1280x1024 @ 120.00 Hz (GTF) hsync: 131.64 kHz; pclk: 233.79 MHz
Modeline "1280x1024_120.00" 233.79 1280 1384 1528 1776 1024 1025 1028 1097 -HSync +Vsync

Please note that this is not an officially recommended modeline from NVIDIA.

--andy