warren> 2: A somewhat similar thing would happen with the Ascend TNT warren> Max, which had side-to-side airflow. These were dial termination warren> boxes, and so people would install racks and racks of them. The warren> first one would draw in cool air on the left, heat it up and warren> ship it out the right. The next one over would draw in warm air warren> on the left, heat it up further, and ship it out the warren> right... Somewhere there is a fairly famous photo of a rack of warren> TNT Maxes, with the final one literally on fire, and still warren> passing packets. The Ascend MAX (TNT was the T3 version, max took 2 T1s) was originally an ISDN device. We got the first v.34 rockwell modem version for testing. An individual card had 4 daughter boards. They were burned in for 24 hours at Ascend, then shipped to us. We were doing stress testing in Fairfax VA. Turns out that the boards started to overheat at about 30 hours and caught fire a few hours after that... Completely melted the daughterboards. They did fix that issue and upped the burnin test period to 48 hours. And yeah, they vented side to side. They were designed for enclosed racks where are flow was forced up. We were colocating at telco POPs so we had to use center mount open relay racks. The air flow was as you describe. Good time. Had by all... Both we (UUNET, for MSN and Earthlink) and AOL were using these for dialup access. 80k ports before we switched to the TNTs, 3+ million ports on TNTs by the time I stopped paying attention.