amd64/123495: 7.0 AMD64 doesn't install on a Dell SC1435

Dieter freebsd at
Wed May 7 17:41:02 UTC 2008

In message <200805071621.m47GLbCD018315 at>, Randy Schultz writes:
> FBSD 6.x AMD64 works great on this system, as does centos linux.  When I try to install 7.0 (AMD64 of course), on boot (of
>f the cdrom) I notice:
>    ad4: DMA limited to UDMA33, device found non-ATA66 cable
> Not sure if that is an important clue but it seems to be.  I know my cables are SATA-II, FWIW.

This means the kernel thinks that ad4 is PATA connected with a 40 wire cable
rather than an 80 wire cable.  (connector is 40 pins either way, extra wires
are grounds)

If ad4 is a PATA hard drive, it just means that the speed is limited to 33 MBps
due to the old style cable.

If there are no PATA hard drives connected, then this is an important clue.

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