Still having ServerWorks HT1000 drive problems

I have a Dell rackmount server with the HT1000 chipset and two 160GB SATA
drives.  As of a recent kernel build, I'm still getting drive-related
lockups.

$ uname -a
FreeBSD jail3.daycos.com 7.0-PRERELEASE FreeBSD 7.0-PRERELEASE #1: Tue Jan 15 10:55:06 CST 2008     root_at_jail3.daycos.com:/usr/obj/usr/src/sys/GENERIC  amd64

$ dmesg | grep -i ata
atapci0: <ServerWorks HT1000 SATA150 controller> port 0xecb0-0xecb7,0xeca0-0xeca3,0xecb8-0xecbf,0xeca4-0xeca7,0xece0-0xecef mem 0xefdfe000-0xefdfffff irq 6 at device 14.0 on pci3
atapci0: [ITHREAD]
ata2: <ATA channel 0> on atapci0
ata2: [ITHREAD]
ata3: <ATA channel 1> on atapci0
ata3: [ITHREAD]
atapci1: <ServerWorks HT1000 UDMA100 controller> port 0x1f0-0x1f7,0x3f6,0x170-0x177,0x376,0x8c0-0x8cf at device 2.1 on pci0
ata0: <ATA channel 0> on atapci1
ata0: [ITHREAD]
ata1: <ATA channel 1> on atapci1
ata1: [ITHREAD]
acd0: CDROM <HL-DT-ST GCR-8240N/1.10> at ata0-master PIO4
ad4: 152587MB <WDC WD1600JS-75NCB3 10.02E04> at ata2-master PIO4
ad6: 152587MB <WDC WD1600JS-75NCB3 10.02E04> at ata3-master PIO4

The PIO4 mode is because I have DMA disabled in loader.conf.  That was the
only way I could find to keep the system stable.  Whenever I used atacontrol
to set UDMA133 mode, I immediately got the "non-ATA66 cable" warning and
then soon started seeing DMA timeouts:

Jan 15 11:10:42 jail3 kernel: ad4: DMA limited to UDMA33, device found non-ATA66 cable
Jan 15 11:11:07 jail3 ntpd[628]: kernel time sync enabled 2001
Jan 15 11:13:00 jail3 kernel: NMI ISA NMI ISA 20, EISA f2f0,
Jan 15 11:13:00 jail3 kernel: N N
Jan 15 11:13:00 jail3 kernel:
Jan 15 11:13:00 jail3 kernel: <<
Jan 15 11:13:00 jail3 kernel: 22<>>EM2I>ISM AII  ISfSfA
Jan 15 11:13:00 jail3 kernel: A
Jan 15 11:13:00 jail3 kernel: 20, EIS3A0 ,f fE
Jan 15 11:13:00 jail3 kernel: I
Jan 15 11:13:00 jail3 kernel: SA ff
Jan 15 11:13:17 jail3 kernel: ad4: TIMEOUT - WRITE_DMA retrying (1 retry left) LBA=8129551
Jan 15 11:13:17 jail3 kernel: NMI ISA 20, EISA ff
Jan 15 11:13:17 jail3 kernel: NMI ISA 20, EISA ff
Jan 15 11:13:17 jail3 kernel: NM<I ISA2 >NMI ISA 30, EIS3A0 , fEfI
Jan 15 11:13:17 jail3 kernel: S
Jan 15 11:13:17 jail3 kernel: A ff
Jan 15 11:13:17 jail3 kernel: ad4: WARNING - SETFEATURES SET TRANSFER MODE taskqueue timeout - completing request directly
Jan 15 11:13:17 jail3 kernel: ad4: TIMEOUT - WRITE_DMA retrying (0 retries left) LBA=8129551
Jan 15 11:13:17 jail3 kernel: NMI ISA 20, EISA fNfM
Jan 15 11:13:17 jail3 kernel: I
Jan 15 11:13:17 jail3 kernel: ISA 20, EISA ff
Jan 15 11:13:17 jail3 kernel: NMI ISAN M3I0 ,I ESISAA  ff3
Jan 15 11:13:17 jail3 kernel: 0
Jan 15 11:13:17 jail3 kernel: , EISA ff
Jan 15 11:13:17 jail3 kernel: ad4: FAILURE - WRITE_DMA timed out LBA=8129551
Jan 15 11:13:17 jail3 kernel: GEOM_MIRROR: Request failed (error=5). ad4s1d[WRITE(offset=1477943296, length=131072)]
Jan 15 11:13:17 jail3 kernel: g_vfs_done():mirror/mirror1e[WRITE(offset=404193280, length=131072)]error = 5
Jan 15 11:13:17 jail3 kernel: ad4: WARNING - SETFEATURES SET TRANSFER MODE freeing taskqueue zombie request

Is there anything else I could try?  There's nowhere in the BIOS to switch
between PATA and SATA modes, so I don't know of any way to see if that
would make a difference.
-- 
Kirk Strauser