I'm using a viewsonic 19" LCD monitor with a powermac 7100/66. The only resolution available in the monitor control panel is 640x480. The viewsonic gives me a message to use 1440x900. The mac specs state it's capable of 1152x870 @ 8 bit. Help!

For unsupported resolutions, one may need to see if there are any software

solutions; maybe the minimum specs of the display are not met by an 8-bit

color specification of the video card in the computer.

Does the display support two kinds of connections, another one, plus VGA?

Could be the display needs some other support for it to work. Drivers?

VRAM? A different control panel and (third-party) software?

The limits may vary due to the VRAM on the card. With enough there, and

with a VGA connection (or supported converter to/from older Mac DB-15)

and the video graphics card with minimal supported specs will show that.

Been several years since I've run any PowerMac, & only used a variety of

Apple CRT color displays with them. Most times, they were very adequate.

A wider array of original choices appeared in the Displays control panel...

So I suspect the lack of video support in the graphics card or VRAM, to be

a player in this resolution limit you see in the control panel. A later CPU/GPU

and better hardware, later Mac OS, offered greater support for newer driver

along with better results.

There may not be a workable upgrade to a different graphic video card for

that old a vintage computer; or if there was one, to locate that now may be

a next-to-impossible mission. Was there any hints in the web site for older

Macs, the LowEndMac site, or others? Some are no longer current sites.

In any event...

Good luck & happy computing! 🙂

PS: There used to be an application or utility to change resolutions, I'd

tried this one back in the day -- don't think the current version will help:

SwitchResX http://www.madrau.com/ - had been around since 1997...

The author of this item may have a vintage version in archive... (?)

http://www.madrau.com/SRXv3/html/SR2/indexSR2.html

Not sure if that'd help. Above post timed out while I was looking through

several years worth of bookmarks to try & find a relevant older one.

{Another item was to use OS9 Forever in older PM8500, for upgrades

plus newer expansion cards, including USB, etc.}

There should be an easy answer...

Good luck & happy computing! 🙂

edited

You may need to explore eBay or the LEM Swap List for a graphics card for that machine. It could take a while.

It took some fiddling to get a small wide-screen monitor to work with my 9600. I had to do it, because my old 20" Apple MultipleScan CRT died after 14 years of use (!!!). It started up in an undesirable resolution, but somehow or other I was able to get it going. I think I remember an option in the OS 8.6 or 9 control panel to show all resolutions. There are more card options for that generation than there are for a Nubus Mac. I put an original Radeon Mac Edition PCI card in the 9600.

"The viewsonic gives me a message to use 1440x900. The mac specs state it's capable of 1152x870 @ 8 bit."

With the logic board's onboard HDI-45 video port and an "HDI-45 to Mac DB-15" adapter, you can connect any of a number of older Apple displays having up to a 17" screen size. If you have the video card installed in the PDS slot, its 2 MBs of VRAM enable the use of a 19" or 20" or 21" display. These are the older CRT-type with a 4:3 aspect ratio, such as the Macintosh 19" Color Display (1024 x 768), the Apple Multi-Scan 20" Display (1280 x 1024), and the Macintosh 21" Color Display (1152 x 870). Unfortunately, the 16:9 aspect ratio came along years after the older video cards were designed for the NuBus Power Macs (6100s, 7100s, and 8100s). Your ViewSonic's optimal resolution/refresh rate setting of 1440x900 @ 60 Hz isn't available.

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