Turn monitor off in console mode Linux on an iMac G3

Recently I acquired an old Bondi Blue iMac G3 with a PowerPC @266Mhz and 64MB RAM. I upgraded the RAM to 128MB and installed Debian GNU/Linux on it. Runs like a charm. I intend to use it remotely to test big-endian compilations, so I wanted the built-in monitor to be turned off. After searching the net extensively, I was unable to find a solution. setterm -blank 1 does not work (no APM support on a G3), xdpms doesn't work either (no DPMS) and pmset is only available under Mac OS X. I did find a solution though. If you configure Xorg wrongly and select a resolution the monitor can't cope with, it turns itself off. I'd rather not have X installed, but well, a dark server closet is worth the extra few megabytes of disk space And if I need the console because I locked myself out remotely or something, CTRL-ALT-F1 brings back the framebuffer console and turns on the monitor again.