Hi, I've just upgraded to an Athlon+KT133 from a P3+pro133 setup. For the old motherboard which had a 596b southbridge I got perfect udma66 support form my hard drives. After I switched over, and without changing anything except switching from p3 to athlon optimisations, the driver reports my drives running at udma33. This is despite detecting an 80w cable, using ide0=ata66 and turning word93 checking off. The new southbridge is a 686b. Also, possibly semi-related; it insists on detecting my ls-120 drive as udma22 even though mwdma11 is the best it can actually do. I'm not experiencing any corruption, fingers crossed ( I understand that that was traced to an acpi conflict? ) but this is nevertheless incorrect behaviour. /proc/ide/via: ----------VIA BusMastering IDE Configuration---------------- Driver Version: 3.20 South Bridge: VIA vt82c686b Revision: ISA 0x40 IDE 0x6 BM-DMA base: 0xd000 PCI clock: 33MHz Master Read Cycle IRDY: 0ws Master Write Cycle IRDY: 0ws BM IDE Status Register Read Retry: yes Max DRDY Pulse Width: No limit -----------------------Primary IDE-------Secondary IDE------ Read DMA FIFO flush: yes yes End Sector FIFO flush: no no Prefetch Buffer: no no Post Write Buffer: no no Enabled: yes yes Simplex only: no no Cable Type: 80w 80w -------------------drive0----drive1----drive2----drive3----- Transfer Mode: UDMA UDMA UDMA UDMA Address Setup: 30ns 30ns 30ns 60ns Cmd Active: 90ns 90ns 90ns 90ns Cmd Recovery: 30ns 30ns 90ns 90ns Data Active: 90ns 90ns 90ns 90ns Data Recovery: 30ns 30ns 30ns 90ns Cycle Time: 60ns 60ns 60ns 90ns Transfer Rate: 33.3MB/s 33.3MB/s 33.3MB/s 22.2MB/s and relevant dmesg: Uniform Multi-Platform E-IDE driver Revision: 6.31 ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx VP_IDE: IDE controller on PCI bus 00 dev 39 VP_IDE: chipset revision 6 VP_IDE: not 100% native mode: will probe irqs later VP_IDE: VIA vt82c686b (rev 40) IDE UDMA100 controller on pci00:07.1 VP_IDE: ATA-66/100 forced bit set (WARNING)!! ide0: BM-DMA at 0xd000-0xd007, BIOS settings: hda:DMA, hdb:DMA ide1: BM-DMA at 0xd008-0xd00f, BIOS settings: hdc:DMA, hdd:DMA hda: IBM-DPTA-372730, ATA DISK drive hdb: QUANTUM FIREBALL CX6.4A, ATA DISK drive hdc: TOSHIBA DVD-ROM SD-M1212, ATAPI CD/DVD-ROM drive hdd: LS-120 VER5 00 UHD Floppy, ATAPI FLOPPY drive ide0 at 0x1f0-0x1f7,0x3f6 on irq 14 ide1 at 0x170-0x177,0x376 on irq 15 hda: 53464320 sectors (27374 MB) w/1961KiB Cache, CHS=3328/255/63, UDMA(33) hdb: 12594960 sectors (6449 MB) w/418KiB Cache, CHS=784/255/63, UDMA(33) hdc: ATAPI 32X DVD-ROM drive, 256kB Cache, UDMA(33) Uniform CD-ROM driver Revision: 3.12 hdd: 123264kB, 963/8/32 CHS, 533 kBps, 512 sector size, 720 rpm ide-floppy: hdd: I/O error, pc = 5a, key = 5, asc = 24, ascq = 0 hdparm reports that the drives are udma66 capable which is correct, but how do I convince the driver to use it? thanks, --phil - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/