Does anyone know whether the following two hard drives are compatible? I have an old IBM (notebook) hard drive with the following specs: AT Interface (Enhanced IDE) conforming to ATA-5 ULTRA DMA Mode 5 Storage: 30 GB Interface transfer rate: 100 MB/s I am planning to replace it with a new hard drive with the following specs: ATA-6 ULTRA DMA Mode 5 Storage: 40 GB Interface transfer rate: 100 MB/s The one that is bothering me is the sentence:"AT Interface (Enhanced IDE) conforming to ATA-5". Does this mean the interface is ATA-5? Can ATA-5 interface recognize an ATA-6 hard drive? Thank you.

Your ATA6 HDD is backwards compatible, and an ATA5 controller will handle it just fine as long as it IS an ATA5 controller.

Something wrong somewhere. I believe: ATA5 is UDMA4 66mhz ATA6 is UDMA5 100mhz But, like Tropic said ATA6 is backward compatible. The drive will run at 66mhz and not 100mhz, but that's not a big deal.

Thanks a bunch, guys! I have ordered the new hard drive (ATA-6, 7200 RPM, 60 GB). ;p

I also bought an ATA-6 hard drive for my Dell laptop but the new drive cannot be detected by BIOS. I have the latest BIOS an it seems Dell has an ATA-6 hard drive for my model but I couldn't get much help from Dell support as I bought this hard drive myself. Do I need to install any drivers? If not, how should I make the BIOS see the drive? It is a Toshiba drive. Thanks, -Jalil

Have to jump in with similar question. I have a Compaq Presario 1800T with the Toshiba MK3017GAP 30GB ATA-5 drive and would also like to replace it with the HITACHI 60GB 7200RPM Travelstar 7K60 Internal ATA-6 but am also worried that my BIOS won't recognize it. Any thoughts? Thanks guys