amd64 ad0: TIMEOUT - READ_DMA on boot...

Jeff D. Hamann jeff.hamann at
Wed Sep 7 16:58:50 PDT 2005

I'm trying to set up a new amd64 FreeBSD 5.4 machine and when I attempt to 
boot up for the first time (many time by now), I get the following 

isa_dmainit(2, 40960) failed

blah, blah, blah, then...

ad0: 190782MB <WDC WD2000JB-00GVA0/08.02D08> [387621/16/53] at ata0-master 
ad0: TIMEOUT - READ_DMA retrying (2 retries left) LBA=390721905

and then the system just hangs and does nothing. I've tried swapping out the 
IDE cable, same result

I've seen some other posts regarding this error and haven't seen a solution. 
Also, I don't know how to get a dump of the boot process.

The hard drive is a brand new western digital 200 GB drive as well.

Is this a problem with the amd64 or the 5.4 release or bad hardware or what?

Please help,

Jeff D. Hamann
Forest Informatics, Inc.
PO Box 1421
Corvallis, Oregon USA 97339-1421
jeff.hamann at

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