Did you try xmodule=nv or xmodule=vesa for generic vesa graphics?
can't boot Knoppix 4.0.2 on my PC: i'm on a CeleronD330 based system, mounting an Asus P4S800-MX SE main board (chipset: SiS 661FX), and a GeForce FX5500 graphics accelerator... the display is normally set to 1024x768 pixel, with a refresh rate of 60Hz...
when i was just using the main board's integrated graphics system, Knoppix was booting up correctly... but now that i installed the GeForce accelerator, the X Window system won't start: the monitor just goes black after all booting tasks seemed to complete successfully...
i've tried all suggested techniques, but no cheat code seems to work:
# boot: knoppix vga=0
# boot: knoppix acpi=off pnpbios=off noapic noapm
# boot: knoppix vga=0 debug -b 3
# boot: failsafe debug -b 3
# boot: knoppix screen=1024x768 xvrefresh=75
# boot: knoppix screen=800x600 xvrefresh=60
none of the above does anything...
the .iso CD image was burnt correctly (using NERO with the right setup for .iso images), and it actually booted up alright before the Geforce accelerator was installed...
i've got another PC (a Pentium 4), mounting a GeForce MX 420 graphics accelerator... and Knoppix won't boot up on that one either... i don't know, maybe Knoppix doesn't like GeForce... weird... apparently, it's easier to install Linux on an Xbox than booting Knoppix on PC...
Did you try xmodule=nv or xmodule=vesa for generic vesa graphics?
perhaps a silly question - but can you boot into any OS ? a winXP CD perhaps ?
I ask because, i wonder if you have disabled the Onboard Graphics in the BIOS - and had you successfully removed the Drivers ? (in windoze Add/Remove Programs in Control Panel) -- you said that it boots fine previously, before the GeForce 5500 Adapter install...but don't mention whether or not you can successfully switch back and forth via Enabling/Disabling Onboard graphics in the BIOS.
You should be able to boot into a standard VGA display adapter without Either the Onboard graphics or the Video Card installed (BTW - the 5500 is AGP, yes ?)
Do you know how to uninstall old and install new hardware ? ...In windoze, you would boot into safe mode and remove the Onboard graphics accelerator drivers from Add/Remove Programs, as i noted above -- then shutdown normally, Unplug from wall (or pull ATX power cord out of back) , open the case and install the Video Card (Display Adapter/GeForce FX5500).
Then plug in, and Boot directly into the BIOS and;
* Disable the Onboard Graphics system
* Set "Primary Display Adapter" as AGP (for an AGP card , PCI for PCI card)
* check the aperture size and other AGP port settings, like voltages
* Exit the BIOS Saving Changes....
Upon Boot, you will/should be prompted for the Drivers for the New Video Card -- or you can elect to just use the Standard VGA adapter
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