Video Problem: Only Top Half of Characters

I am having a funny problem with Knoppix 6.4.4. This shows up with both the CD and DVD versions. They work fine on five different machines I tried, but on one particular one the video is messed up. Its regular OS is Fedora 14 with the "nouveau" driver, and that works fine. Processor is a Sempron 3400 with 4 GB RAM.

The complete lspci output is at the end of this posting, but here are the specs on the video controller --
00:0d.0 VGA compatible controller: nVidia Corporation C61 [GeForce 6100 nForce 405] (rev a2) (prog-if 00 [VGA controller])

Here's what happens: When it boots, the screen goes through the usual messages. Then it breaks into a series of horizontal stripes, white with dots of red, separated by black stripes. Then the regular Knoppix desktop appears and looks great. But if I try to make the menu appear it pops up but only half of each line appears. That is, for each menu choice the top half of the item appears with the grey background, but the bottom half is transparent, so the desktop shows through. So the menu looks like a series of stripes. And if I open a terminal window and try some commands, again only the top half of each line of characters appears, with just background where the lower half should be.

I tried booting with some options, such as xmodule=nv, xmodule=vesa, vga=normal, and vga=0. one at a time, of course. Same results with every option.

I hope all this is clear. Any ideas?

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Here is the result of my lspci -v :

00:00.0 RAM memory: nVidia Corporation MCP61 Memory Controller (rev a1)
Subsystem: Elitegroup Computer Systems Device 2602
Flags: bus master, 66MHz, fast devsel, latency 0
Capabilities: <access denied>

00:01.0 ISA bridge: nVidia Corporation MCP61 LPC Bridge (rev a2)
Subsystem: Elitegroup Computer Systems Device 2602
Flags: bus master, 66MHz, fast devsel, latency 0

00:01.1 SMBus: nVidia Corporation MCP61 SMBus (rev a2)
Subsystem: Elitegroup Computer Systems Device 2602
Flags: 66MHz, fast devsel, IRQ 10
I/O ports at fc00 [size=64]
I/O ports at 1c00 [size=64]
I/O ports at f400 [size=64]
Capabilities: <access denied>
Kernel driver in use: nForce2_smbus
Kernel modules: i2c-nforce2

00:01.2 RAM memory: nVidia Corporation MCP61 Memory Controller (rev a2)
Subsystem: Elitegroup Computer Systems Device 2602
Flags: 66MHz, fast devsel

00:02.0 USB Controller: nVidia Corporation MCP61 USB Controller (rev a3) (prog-if 10 [OHCI])
Subsystem: Elitegroup Computer Systems Device 2602
Flags: bus master, 66MHz, fast devsel, latency 0, IRQ 22
Memory at fe02f000 (32-bit, non-prefetchable) [size=4K]
Capabilities: <access denied>
Kernel driver in use: ohci_hcd

00:02.1 USB Controller: nVidia Corporation MCP61 USB Controller (rev a3) (prog-if 20 [EHCI])
Subsystem: Elitegroup Computer Systems Device 2602
Flags: bus master, 66MHz, fast devsel, latency 0, IRQ 23
Memory at fe02e000 (32-bit, non-prefetchable) [size=256]
Capabilities: <access denied>
Kernel driver in use: ehci_hcd

00:04.0 PCI bridge: nVidia Corporation MCP61 PCI bridge (rev a1) (prog-if 01 [Subtractive decode])
Flags: bus master, 66MHz, fast devsel, latency 0
Bus: primary=00, secondary=01, subordinate=01, sec-latency=32
I/O behind bridge: 0000b000-0000cfff
Memory behind bridge: fdf00000-fdffffff
Prefetchable memory behind bridge: fd800000-fd8fffff
Capabilities: <access denied>

00:05.0 Audio device: nVidia Corporation MCP61 High Definition Audio (rev a2)
Subsystem: Elitegroup Computer Systems Device a88d
Flags: bus master, 66MHz, fast devsel, latency 0, IRQ 22
Memory at fe028000 (32-bit, non-prefetchable) [size=16K]
Capabilities: <access denied>
Kernel driver in use: HDA Intel
Kernel modules: snd-hda-intel

00:06.0 IDE interface: nVidia Corporation MCP61 IDE (rev a2) (prog-if 8a [Master SecP PriP])
Subsystem: Elitegroup Computer Systems Device 2602
Flags: bus master, 66MHz, fast devsel, latency 0
[virtual] Memory at 000001f0 (32-bit, non-prefetchable) [size=8]
[virtual] Memory at 000003f0 (type 3, non-prefetchable) [size=1]
[virtual] Memory at 00000170 (32-bit, non-prefetchable) [size=8]
[virtual] Memory at 00000370 (type 3, non-prefetchable) [size=1]
I/O ports at f000 [size=16]
Capabilities: <access denied>
Kernel driver in use: pata_amd
Kernel modules: ata_generic, pata_acpi, pata_amd

00:07.0 Bridge: nVidia Corporation MCP61 Ethernet (rev a2)
Subsystem: Elitegroup Computer Systems Device 2602
Flags: bus master, 66MHz, fast devsel, latency 0, IRQ 43
Memory at fe02d000 (32-bit, non-prefetchable) [size=4K]
I/O ports at ec00 [size=8]
Capabilities: <access denied>
Kernel driver in use: forcedeth
Kernel modules: forcedeth

00:08.0 IDE interface: nVidia Corporation MCP61 SATA Controller (rev a2) (prog-if 85 [Master SecO PriO])
Subsystem: Elitegroup Computer Systems Device 2602
Flags: bus master, 66MHz, fast devsel, latency 0, IRQ 20
I/O ports at 09f0 [size=8]
I/O ports at 0bf0 [size=4]
I/O ports at 0970 [size=8]
I/O ports at 0b70 [size=4]
I/O ports at d800 [size=16]
Memory at fe02c000 (32-bit, non-prefetchable) [size=4K]
Capabilities: <access denied>
Kernel driver in use: sata_nv
Kernel modules: ata_generic, pata_acpi, sata_nv

00:09.0 PCI bridge: nVidia Corporation MCP61 PCI Express bridge (rev a2) (prog-if 00 [Normal decode])
Flags: bus master, fast devsel, latency 0
Bus: primary=00, secondary=02, subordinate=02, sec-latency=0
I/O behind bridge: 0000a000-0000afff
Memory behind bridge: fde00000-fdefffff
Prefetchable memory behind bridge: 00000000fdd00000-00000000fddfffff
Capabilities: <access denied>
Kernel driver in use: pcieport
Kernel modules: shpchp

00:0b.0 PCI bridge: nVidia Corporation MCP61 PCI Express bridge (rev a2) (prog-if 00 [Normal decode])
Flags: bus master, fast devsel, latency 0
Bus: primary=00, secondary=03, subordinate=03, sec-latency=0
I/O behind bridge: 00009000-00009fff
Memory behind bridge: fdc00000-fdcfffff
Prefetchable memory behind bridge: 00000000fdb00000-00000000fdbfffff
Capabilities: <access denied>
Kernel driver in use: pcieport
Kernel modules: shpchp

00:0c.0 PCI bridge: nVidia Corporation MCP61 PCI Express bridge (rev a2) (prog-if 00 [Normal decode])
Flags: bus master, fast devsel, latency 0
Bus: primary=00, secondary=04, subordinate=04, sec-latency=0
I/O behind bridge: 00008000-00008fff
Memory behind bridge: fda00000-fdafffff
Prefetchable memory behind bridge: 00000000fd900000-00000000fd9fffff
Capabilities: <access denied>
Kernel driver in use: pcieport
Kernel modules: shpchp

00:0d.0 VGA compatible controller: nVidia Corporation C61 [GeForce 6100 nForce 405] (rev a2) (prog-if 00 [VGA controller])
Subsystem: Elitegroup Computer Systems Device 2602
Flags: bus master, 66MHz, fast devsel, latency 0, IRQ 21
Memory at fb000000 (32-bit, non-prefetchable) [size=16M]
Memory at e0000000 (64-bit, prefetchable) [size=256M]
Memory at fc000000 (64-bit, non-prefetchable) [size=16M]
[virtual] Expansion ROM at f4000000 [disabled] [size=128K]
Capabilities: <access denied>
Kernel driver in use: nouveau
Kernel modules: nouveau, nvidiafb

00:18.0 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] HyperTransport Technology Configuration
Flags: fast devsel
Capabilities: <access denied>

00:18.1 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] Address Map
Flags: fast devsel

00:18.2 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] DRAM Controller
Flags: fast devsel
Kernel modules: amd64_edac_mod

00:18.3 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] Miscellaneous Control
Flags: fast devsel
Kernel driver in use: k8temp
Kernel modules: k8temp

01:05.0 SATA controller: Initio Corporation INI-1623 PCI SATA-II Controller (rev 02) (prog-if 00 [Vendor specific])
Subsystem: Initio Corporation INI-1623 PCI SATA-II Controller
Flags: bus master, 66MHz, medium devsel, latency 64, IRQ 16
I/O ports at cc00 [size=256]
I/O ports at c800 [size=256]
I/O ports at c400 [size=256]
I/O ports at c000 [size=256]
I/O ports at bc00 [size=256]
Memory at fdfff000 (32-bit, non-prefetchable) [size=4K]
[virtual] Expansion ROM at fd800000 [disabled] [size=256K]
Capabilities: <access denied>
Kernel driver in use: sata_inic162x
Kernel modules: sata_inic162x

Hi Ciaraldi,

The release notes for Knoppix 6.4.4. (http://www.knopper.net/knoppix/knoppix64-en.html) explain that if you have trouble with nVidia graphics chips/cards, you should try booting with:

Code:

---

knoppix nomodeset xmodule=nv

---

If that doesn't work, the only thing I can think of that might give the symptoms you see is dust.

Seriously, I had a motherboard with an on-board graphics chip that gave all sorts of weird effects until I got fed up with it and bought a new mother board. As I took the machine apart to remove the 'bad' motherboard I found an astonishing amount of dust behind/beneath the motherboard. I've since put the old motherboard in a new case and, touch wood, it's been fine so far.

This puts me in mind of a weird problem I discovered once on a system I picked up cheap, which had had all sorts of fixes tried and ultimately the owner of the computer shop just dumped it. Simply put, the motherboard MOUNT was defective (one of the screw-in posts missing) and the video card wasn't completely secure. Sometimes fine, but when it got jostled...

Anyway, in your case, if the cheatcode Forester recommended doesn't do the job, it's possible to use the Windows driver using a function called ndiswrapper. A quick search of these forums will give you more details than you can shake a stick at.

Cheers!
Krishna :mrgreen:

Well, I tried the "nomodeset xmodule=nv" option and it worked partially --
Right after booting, clicking on the icon in the lower-right corner makes the main menu appear. But mousing to one of the choices gives the sub-menu, and that only has the top half of each line.
And then when I open a window with an opaque background, such as "Desktop Properties", it is also made up of stripes with the background showing between. If I move the window, it leaves behind very thin stripes. Weird. I will look into the ndiswrapper thing. Remember, it works fine under Fedora 14 with the nv driver.