X230GV@TAMVM1.BITNET (Glenn L Vanderburg) (04/21/87)
Since we're talking about rating printers by things other than pages/minute, I guess I have to put in my two cents worth, since the topic has been on my mind for a while. As a friend of mine said (on a totally unrelated topic), ``Let's nail that sucker down.'' There are actually many things to consider besides ppm. Abhay Bhushan just gave us a pretty thorough LaserWriter vs. Xerox play-by-play with regard to ppm vs. AMPV (Average Monthly Page Volume, or pages per month). But there's more to it than that. You have to consider ``real'' pages per minute, and something that (for want of a better name) we'll call pages per hour. ``Real'' pages per minute is, of course, impossible to measure objectively. This varies from job to job or even from page to page. It can be measured to some extent, though. If you're familiar with the kind of printing people at your site do, and if you have a good idea about what constitutes ``complex'' printing for a laser printer, you can get a good feel for whether or not a printer will suit your needs. Suffice it to say that a printer running PostScript, Interpress, or DDL will suffer severe degradations in this department as page complexity goes up. The weird one is pages per hour. I ran into this with a QMS Lasergrafix 1200 we had here at Texas A&M. It printed fast enough for us, and we were just barely pushing the AMPV barrier, but we had *severe* problems with it. The printer uses the Xerox XP-12 engine (just like a Xerox 2700 or a DEC LN01), and it is apparently inadequately cooled. If we printed plain, simple text on it as fast as it would go (12 ppm) for more than about 40 minutes, we would kill it. The engine would overheat and toner would start sticking to the drum, and the pages would soon have black streaks across them. Pretty sneaky. Of course, maybe it just didn't like us. Of course, you also have to worry about the way these things interact. Plus there are maintenance costs, toner costs, parts availability, etc. to worry about. All vaguely reminiscent of nailing jello to the wall. Regards, Glenn Vanderburg