(11-05-2024, 01:25 PM)echo Wrote: i ordered a 1280x1024 screen to prevent any unforeseen problems. it may take up to a week to arrive.
but i should have the system and the null modem cable in a couple days.
I think you may have misunderstood one of my descriptions regarding how the prom works.
The prom resolution can often not be changed. On Indy that's incorrect and it can be changed to 1024 x 768 on every other station I've seen it is hard set and you cannot change the prom resolution to something else. Just like on a PC how you cannot change your bios resolution, it is what it is.
when the OS starts it always takes default resolution from installation when you first load the operating system. If you fiddle with the resolution in the OS, it will automatically switch at the login screen at every startup before you have a chance to login.
you can switch to any valid monitor resolution using a configuration so the normal booting procedure would be the graphical prom appears at 1280 x 1024, then the screen goes blank momentarily then the login screen appears at whatever you've told the operating system to use. Just like what happens in Windows on a normal PC.
what I warned you against was there is no revert button or undo button or any graphical control of the monitor resolution in the operating system. It's a terminal command. If you mess it up you will have to stay in the prom, in its command terminal in single user mode, or use a serial terminal to undo what you did. So what I said was if you use an invalid monitor mode you can't just reboot out of it. The operating system will be stuck in that mode until you issue the appropriate command while it's running to undo what you did. You issue that command either through the normal modem terminal cable or the graphical prom terminal while running a terminal interface to the running OS (instead of a windowing system). The graphical prom should work unless you have a monitor that doesn't support what the graphical prom normally uses.
however there are ways of screwing up so bad that even the graphical prom doesn't appear. There are various NVRAM options that you can fiddle with at times to make the entire graphical prom skip and just not appear and go right to the operating system. I've seen it happen but I've never purposely caused it to happen.
in the case the graphical prom no longer appears to you you would have to use a serial terminal cable to set things right unless you have an RTC chip with a removable battery that you can pull the battery off of to reset all the NVRAM parameters back to default. This is not normally available as the RTC chips that originally were produced for the SGI's have the battery sealed in the epoxy and there's no way to reset the values using the SGI without the PROM's help, by default. There is no "clear settings" jumper as I mentioned prior. If you screw up the firmware the values can remain trapped in your RTC module and you need to have that cleared. You could use an eprom programmer to clear it or if you can get into the serial terminal and you have a running OS you can use commands to RESET it.
I did not mean to imply that the VFO affects the prom, I meant to tell you if it only affects the operating system and has no effect on the prom so the two have different resolutions that are programmed.
I only said that if you screw around with the VFO and you don't get it right you'll be trapped outside of your own monitor until you get in via other means while the OS is running to fix it. Most the time you can do that through the proms terminal if you stop at prom go into the command mode and issue single user mode. Assuming that all works you can undo what you did and attempt to reboot into full multiuser mode.
but as I said there are ways of forcing a desktop system to think it's headless in the firmware settings. Some people do this because they have some weird problem with seeing the graphical prom screen and any of the startup messages before the operating system starts. I don't understand it myself but they probably are going from more of a clean look where they don't see a couple of the errors that naturally come up on start up. SGI do not have any kind of splash screen or covering logo so you'll see some OS output when you're starting and it can say there's a few errors or issues that are in fact non-issues and I guess because it bothers people they forcibly disable the graphical prom entirely.
The terminal command to set resolutions does not do any kind of checking. It'll let you set to whatever the VFO files are around. So people who experiment with resolutions are going to run into a problem where they're shut out of their own operating system because they chose the wrong setting and their monitor immediately went to sleep or an error that said out of range and now they have to undo that problem. If they also are one of the people that disabled their graphical problems because it "looked bad" now you have to use a serial terminal to correct what you just did.
that is the situation I was describing when you asked why someone would need to have a serial terminal around. That is the scenario. Most of the time your graphical PROM will be there with your keyboard and malfunctioning for you to attempt to fix stuff.
The only other time you would use a serial terminal is if your hardware was not fully booting you could sometimes get a little bit of output to tell where in the process it was starting it's the error is occurring and try to make repairs. You might get no output at all but most of the time you get a little bit of something if the machine is half alive.
I personally think it looks uglier than sin to have a misshapen desktop resolution because I am trying to mix widescreen and non-widescreen resolutions. I wouldn't necessarily mind if the prom screen was stretched on a wide screen display because I'm not going to see it that often. But since I have to configure every SGI I would own to use that widescreen display and I own a lot of machines I'm not going to do that. And just makes no sense. If you own one or two machines sure do what makes you feel good. I'm just saying that at the end of the day your equipment needs to work with the default settings because after you lose an RTC battery or you reload your operating system you'll be back at defaults and if defaults don't work you're once again trapped.
this is again why I advised you not to change the ID of the drive that boots from the default and why you shouldn't go renaming the startup files from the default and why you need to have a monitor that works with the default.
also while it wouldn't necessarily affect your system unless you buy a DCD that has DVI for your octane2. DVI based SGI's work in both an analog and digital DVI modes. Which are separate interface pins on the connector. Which is the combination used by DVI-I. Users that attempt to put an HDMI adapter on the end of the DVI will no longer be able to see the prom screen because the prom screen appears as an analog VGA signal under DVI-A, while the OS appears under a modern DVI-D signal. This is another reason why someone may not see their prom but can see their desktop. But it only affects SGI's that have a DVI connector of which there are very few.
so in summation, you need to have a monitor that supports the default resolution regardless or you can't see the prom at all. Whether you reconfigure with another VFO for a special monitor or screen or projector is your own business. If that device can't see the default resolution you will have trouble working and maintaining the system. And then you'll be forced to use another monitor or a serial terminal to make up the difference. If you fiddle with the OS's resolution the change is instantaneous unless you write some kind of script that undoes what you did if you don't hit a key or something useful. The command is instantaneous. If you get it wrong you'll reboot the OS and you won't even be able to login because the login screen will be an incorrect resolution that you can't see. The other half was explaining that there's no point in getting a widescreen high resolution monitor for a resolution the system can never achieve. If you're attempting to share the monitor with another system and that's all you have that's your own personal choice as long as your heeding the advice that it needs to work in the default resolution well enough for you to see what you're doing.
mine! ...played with in the 90s & long gone: 
NEED -> 
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