View Full Version : 0x50 tech. error and cheat codes

03-26-2009, 07:49 PM

for two days now I have a problem with my Toshiba Satellite PSPA3E Notebook (Graphic: Nvidia GeForce Go 7600)...
Suddenly, without really doing anything, the colors of my screen were messed up and after rebooting I got a BSOD with a 0x50 error at the Nvidia-driver n4_mini.sys (I have Win XP SP2). After a little research I found out that this fault can have many causes - but I'm pretty sure that its the RAM or the graphic card. Unfortunately I can't afford a replacement so I have to come up with a temporary solution. After deinstalling the graphics drivers in safe mode the system worked again - kind of... I now not only have 4bit colors and a resolution of 800x600,
but there are vertical stripes (in rows of four) all over the display. Those stripes are also visible when the computer starts (on the "Toshiba"-logo) - so it can't only be a Windows-fault.
More reasonable would be a physical RAM or a graphic card fault. Then I tried to start Knoppix, but it froze loading the pcmcia card-manager. I got to start the os with the cheat code "failsafe" - suddenly without any graphic problems!
So I know that its possible - as temporary solution - to surpass this error. The problem with failsafe is that my mouse (mousepad or usb) isn't recognized - and I don't know how to load the driver afterwards.
Unfortunately there is no command like "failsafe usb" so that hardware detection is disabled for (alsmost) everything BUT USB.
If I'm writing the failsafe codes by hand (noapic, noapg, nopcmcia etc...) and leave out nousb, the screen is getting really dark (as if contrast would have been set to 0) and mouse clicks aren't registrated somehow.
If I only disable the memory (nodma) it is freezing again at the pcmcia-manager and if I try nodma, noapg and nopcmcia (in any combination), the screen becomes dark again...
So my question is, next to the obvious one: "What can I do / should I try", is whether you can load the failsafe mode with restrictions (e.g. failsafe with usb-support) or if you can explicitly get around the graphic card and the RAM.

Please help me!!!

Thanks already,


PS: (I'm using KNOPPIX_V5.1.1CD-2007-01-04-DE)

Harry Kuhman
03-26-2009, 08:15 PM
.... but I'm pretty sure that its the RAM or the graphic card. ...
First step, test your RAM, which you can do with the Knoppix CD. Boot the disc, and type memtest at the boot prompt. memtest86 should run. Let it run at least through a full pass of all tests, or until an error is reported.

If RAM is OK at least you know that. If it is bad you have little choice but to replace it or at least remove the bad strip if you have multiple SIMMs of memory. The good news is that memory is dirt cheap if you shop around a little (often under $20 U.S. for 4 gig!, and less for smaller amounts). You really don't want to be running with bad memory, you can corrupt data. Of course, you can pay a lot more if you don't shop for sales.

If it's a video problem and it's a notebook you may have no good way to repair it, but I would look at all of the BIOS settings before giving up. At the very least reset the BIOS to defaut settings and try again, maybe something has been changed and caused a critical timing issue.

03-27-2009, 01:42 PM
Thanks for your quick reply!
I didn't know that Knoppix included memetest86...

So I let it run for the last 15 hours, then i cancelled it because it didn't find any errors whatsoever and I had to work.
It seems to be my graphic card!

Then again back to my question... Since graphics in Knoppix look fine when I boot in failsafe mode - only all the other hardware isn't supported - is there any way to boot knoppix without graphics but with support for everything else (and still work in x window)? Or is there any way to get the needed hardware recognized (usb etc...) in the console after booting in failsafe mode?

Thanks again,


03-27-2009, 06:14 PM

I mean its working in failsafe mode, so there must be a way, right?

Harry Kuhman
03-27-2009, 08:38 PM

I mean its working in failsafe mode, so there must be a way, right?
Patience. Not everyone is on your schedule, this is my first time checking into the board today.

Well, if the memory is OK and if the video itself is bad, then you do have a pretty serious problem. And your report of the manufacturer's logo being distorted seems to support that. But if you want to try to run only in text mode and no GUI, you should be able to do that by typing knoppix 2 at the boot prompt. See the cheat codes document (it comes along with a torrent download or read the cheat codes section of the wiki) for more details and options.

03-27-2009, 08:57 PM
I didn't mean to be pushy, I'm sorry...

I've already tried any possible cheat code that I guessed could matter:
nodma, nopcmcia, noagp, vga=normal, vga=0, vsync=60, hsync=60, fb800x600, fbdev800x600, xmodule=nv, pci=biosirq - nothing really changed the outcome

I also tried to go into textmode with knoppix 2 and install the nvidia-driver afterwards but i couldn't really find the driver and anyhow if its broken it won't work. As i said - it only works in failsafe because that mode loads something similar to "vgasave" in win I guess that makes it work...

The only time the graphics are good is when I go into failsafe. I mean all i need is failsafe with support for wifi & mouse - that should be possible somehow, right?

Harry Kuhman
03-27-2009, 10:33 PM
There is a cheat code for vesa that might help (I'll leave it to you to look it up), but if that doesn't work I don't have any other suggestions. Does sound like something may be pretty wrong with the video, and that's hard to pin down remotely. Might even be something about failsafe that seems to bypass whatever the problem is, such as running the video at a lower than normal resolution.