CustomVideoMode: clarification of manual

[carolus]

I do not understand the following instructions from the manual for CustomVideoMode:

The VESA mode IDs for custom video modes start at 0x160. In order to use the above defined custom video mode, the following command line has be supplied to Linux:

vga = 0x200 | 0x160
vga = 864

"supplied to Linux" means how? Clearly not just entering at the command prompt, since the second command would overwrite the first. And does this refer to a linux host or to a linux guest?

[mpack]

How is this question relevant to the "Windows Hosts" forum? I would simply move the topic except that you have provided almost no background information.

[carolus]

How is this question relevant to the "Windows Hosts" forum? I would simply move the topic except that you have provided almost no background information.

I am trying to get Puppy Linux to work in vbox on W7 and am having troubles with the screen resolution. Someone suggested using CustomVideoMode so I looked that up in the manual. The passage I quoted looked important but was incomprehensible to me, so I am asking for an explanation.

If there is a more appropriate forum, please move the thread.

[Perryg]

Moving to Linux guest

[Perryg]

I don't think that the custom settings in VBox will actually help in this matter. What you need to do is set the guest resolution. Usually installing the guest additions (in the guest) takes care of this but if for some reason you can not (I have not tested puppy) then you change the screen resolutions in the /etc/X11/xorg.conf

If you do not use X (CLI mode only) then you need to set the framebuffers in the kernel boot line of your boot loader.

[loukingjr]

for what it's worth and this won't help but the various Puppies are a huge pain trying to get the GAs to work. I gave up ages ago.

[carolus]

for what it's worth and this won't help but the various Puppies are a huge pain trying to get the GAs to work. I gave up ages ago.

It seems always to be a pain to install guest additions in a live distro running from the .iso, but I don't need guest additions just to play with a new distro. There has been no problem with puppies prior to the current "Precise" series, which defaults to a resolution larger than my screen so that I have to scroll to see the whole desktop. Scrolling is a real pain without mouse pointer integration, since I have to switch focus to scroll. If I set a lower resolution within puppy, the window size decreases but the desktop does not shrink in proportion, so that part of the desktop is missing.

VMware Player has a setting for maximum allowed resolution, which forces the new puppy to behave. I was thinking CustomVideoMode might work similarly, but it seems only to enable an option but not force the guest to use it. Perhaps I am missing something important in the section of TFM that I can't understand.

[carolus]

Usually installing the guest additions (in the guest) takes care of this but if for some reason you can not (I have not tested puppy) then you change the screen resolutions in the /etc/X11/xorg.conf

I'm running from a live .iso without guest additions, just to try out the new distro. Reducing the screen resolution to fit my display using xrandr shrinks the window but not the desktop, so that part of the desktop is missing.

[Perryg]

I don't know if this will help because you have not installed the live cd but there is a section to set the max display in the preferences of VirtualBox. See screen shot. ( this should be in the 4.2.6 version IIRC but not sure since I use a version from the future ).

Display.png (46.64 KiB) Viewed 3484 times

[carolus]

I don't know if this will help because you have not installed the live cd but there is a section to set the max display in the preferences of VirtualBox. See screen shot. ( this should be in the 4.2.6 version IIRC but not sure since I use a version from the future ).

Thanks. That option is not present in the version I'm using (4.1.8 ). I don't want to monkey with my working VM's, but I'll try out the newest version of vbox on an old machine.

[carolus]

( this should be in the 4.2.6 version IIRC but not sure since I use a version from the future ).

Nope, not there yet.

[Perryg]

I just checked and the feature is in version 4.2.6

[carolus]

Found the feature under generic "Preferences". (If it worked, I would want to apply it only to the Puppy live iso and not to other VM's, but it does not seem to work.) The options are: automatic, hint, or none. I chose "hint", set it to 800x600, and rebooted the guest. It seemed to make no difference. Again the desktop was larger than my screen, and setting the resolution to 800x600 within the guest led to a smaller window that showed only part of the desktop.

[Martin]

The visible size of the desktop inside your guest depends on the X server configuration of this Linux live CD. You need to check if the window manager or X server is able to change the virtual monitor size dynamically.

[carolus]

The visible size of the desktop inside your guest depends on the X server configuration of this Linux live CD. You need to check if the window manager or X server is able to change the virtual monitor size dynamically.

As stated above, reducing the resolution with xrandr (or with the Puppy GUI tools) shrinks the window without shrinking the desktop, so part of the desktop is missing. Puppy uses OpenBox, which does not seem to have its own resolution setting, according to a bit of googling.

This is not a priority problem for me, and I am about ready to drop the issue, unless someone has a simple suggestion.