SGI: Computer Graphics

Not sure if this is the right forum for this question but since it applies to graphics, I thought I would ask.

Does anyone here know if the O2 can display a 1280x768 display mode @ 60Hz?

Also, can the Octane2 display 1600x1200 also at 60Hz? The Dell monitor that I have attached to my Octane2 has a native 1600x1200 resolution but it is only at 60Hz, and the other monitor I am using for my O2 has a native resolution of 1280x768 also at 60Hz.

I've heard there are some tools that could be installed to add additional display modes but I am not sure what exactly those are and whether or not they will work for what I am asking here. I did try to install the SlimDesk package onto my O2 and that seems to have added some additional modes but they are all higher resolution than my monitor will support.

Thanks!

The xsetmon program should show you what display resolutions your 02 and Octane2 curently support, provided you are running IRIX 6.5.2 (or later).

It's also possible to compile new display modes as well, although it can be a bit of a faf. I managed to compile a 1920x1200 display mode for my O2 which worked fairly well (bit of corruption) and a 1600x900 display mode which worked perfectly.

VFC is the Video Format Compiler for IRIX. It's not installed by default though, so you'll need a set or IRIX CDs in order to add it. A useful page of info I've found which may help is here: http://dart.ncsa.uiuc.edu/slevy/o2-stereo/highres.html

Thanks for the information!

The xsetmon just brings up the standard display modes that are present after a clean installation. I'm hoping to get some different modes that I can fine-tune to work with my monitors a little better.

Does the VFC work on an Octane2 also?

It does, but the VFO files it creates are machine specific. Hence ones you compile on an O2 will not work on an Octane. You'd have to take the source VFS files and re-compile them.

recondas always stands ready to compile custom VFO files for members in good standing *cough* eMGee *cough* .

That worked!

I had to install VFC from the CDs then I created a VFS file for a 1280x768_60 display mode for my O2 and it worked!

Now, I would like to see if I can get a 1600x1200_60 display mode for my Octane2. Will have to tinker around with this some more.

Thanks!

Should be possible, but do note that there's a timing bug with V6/V8 graphics which restricts the pixel clock that they can use. There's some useful information in the wiki about it and which display modes will and won't work on these cards. Of course, if you've got V10/V12, this isn't an issue, plus the issue doesn't apply to the older IMPACT graphics either (although lack of memory restricts what display modes these can handle, although there is a 1600x1200 mode on my SolidIMPACT Indigo2).

vishnu wrote: recondas always stands ready to compile custom VFO files for members in good standing *cough* eMGee *cough* .

For what it's worth, I've had the most first-time's-the-charm success building formats when the recipient provided EDID info for the target monitor. For anyone who'd like to eliminate the middle man from the vfo creation process, there's a template to create a vfo source file from EDID info in this post: viewtopic.php?f=3&t=16727386&p=7357543&#p7357543

I tried the EDID method on my Octane2 with no luck. I'm guessing either I did something wrong or this monitor just isn't going to work.

I downloaded and installed the SwitchResX tool onto my Mac, attached the Dell 2007FP monitor and dumped the EDID info for it, then used that data to build the vfs file, and compiled it. I still get the same results: The display mode does not show up in my list of available modes when I run the Display Properties tool. I even tried to switch over to it using setmon from the console ("setmon -x 1600x1200_60-Dell_2007FP" as I named it) and it still won't switch. After a restart, the computer comes up in 1280x720.

Am I trying to do something here that just may not work? This monitor has a native resolution of 1600x1200@60Hz.

The graphics card is an Odyssey (V8) and I am copying the VFO file into the "/usr/gfx/ucode/ODSY/vof" folder, where they are all located. To make sure this was the actual path, I moved them all out, opened up the display properties tool and of course they were all missing, so I moved them back in.

Maybe I am compiling with the wrong chip and board definitions. The only one I see in the rules folder are the VPro_Chip and VPro_Board def files.

It sounds like others have been successful in getting different Dell monitors to work, so I am guessing I am doing something wrong.

I've found that newly compiled modes have always shown up for me, even when they haven't worked. Make sure that the compiled file has the right extension and is in the correct folder with the other VFO files. Note also that some display adaptors call the compiled files with an SDB extension instead. They're basically the same files, so make sure the extensions of the ones you've compiled match and rename them if they don't.

jmestrada wrote: I tried the EDID method on my Octane2 with no luck. I'm guessing either I did something wrong or this monitor just isn't going to work.

Am I trying to do something here that just may not work? This monitor has a native resolution of 1600x1200@60Hz. The graphics card is an Odyssey (V8)

The first generation of VPro/Odyssey graphics boards (the V6 and V8) suffer from a flaw that won't allow the use of display formats that have a pixel clock that falls between 109 and 193MHz. Unfortunately the pixel clock for a 1600x1200_ 60 display falls into that pixel clock black hole. That's also why the vfo you created doesn't appear in xsetmon.

If your monitor will accept a 72 or 75Hz refresh rate that might bump the pixel clock high enough to work. http://www.nekochan.net/wiki/VPro#VPro_ ... esolutions

An alternative for the V8 would be a 1920x1200_60 display. The pixel clock for most 1920X1200_60 displays is safely on the far side of V8's black hole.

Well that explains it!

Unfortunately this particular model will not support any rates other than 60Hz for 1600x1200. I did plug in my old Samsung SyncMaster 245BW into my Octane2 as a test and was able to display 1920x1200 just fine, I'm tempted to leave this monitor on my Octane and put the Dell onto my Win7 machine.

Guess I need to find another monitor!

Thanks for the info!

Since the only issue is the pixel clock, it's possible to tweak the other parameters of the graphics mode to work around the issue to fit your particular display, say by underclocking the framerate, using different values for the front and back porch or the top and bottom margins (I forgot the proper names) to get a total clock value outside the bad zone. SGI graphics are wonderfully flexible it this regard (but the writing of a graphics mode can be quite daunting). Perhaps using recondas' EDID fill-in-the-values-here vfs as a base would be an idea.

You've got a kick ass Octane2, my recommendation would be to skip getting a new monitor and start saving up your sheckels for a V12. My Octane2 had a V6 when I got it, and the happiest day I've ever spent was the day I swapped that woe-betided V6 for a V12..

I would definitely like to upgrade this to a V12, if I could find one at a reasonable price.

I see a V10 on eBay for sale, but I think I would rather hold out for a V12.

Is there a way to calculate what the pixel clock would be based on the front/back porch settings?

I used the EDID information for this monitor and the template provided to create the vfo file. If there is a way to calculate what the pixel clock would be I can tinker around with it.

Well, I bought the V10 on an impulse. Made the seller an offer of $100 and the took it. I think this will get me by until I come across a V12!

V10 is reasonable enough so long as you can live with the lower texture RAM. If you can, the lack of the pixel clock bug and improved performance are nice. Of course, throw anything with a moderate amount of textures at it and it'll quickly fall behind your V8 for performance!

I figure this will keep me going until I can get a good 24" monitor on it. So now, I'll just have to keep an eye out for a V12 and a dual 600MHz CPU then I will be set!

I'm going to still try and tweak the parameters for the 1600x1200 60Hz mode and see if there is a way to get it to come up. I'll just have to figure out a way to calculate the pixel clock so I can get it in the right range... If that's possible.

Possible, yes. Easy, no. Depending on your LCD, another option is to try dropping the refresh rate. You might be able to get it down to 30-40Hz in order to get within the lower range for example. On an LCD, this isn't as noticeable as you might think for most bits.