On Sat, 2007-11-03 at 12:54 -0400, Ric Moore wrote: > Just for ducks, why would they set the drive to half speed? Think it > might have failed some reliability test at the factory?? Am I about to > bork my drive if I find it set to half-speed and return it to full? I > know that any answer would be pure speculation, but I want to make a > reasonable decision. Quack! As far as I understand it, as mentioned in the instructions for some SATA equipment I had a play with some time ago, it was to make the drives compatible with older 1.5 Gig/sec host hardware. That point of view is re-inforced on a wikipedia page, but I never know how much to trust those pages. http://en.wikipedia.org/wiki/Serial_ATA >From the "SATA 3.0 Gbit/s" section: "Backward compatibility between SATA 1.5 Gbit/s controllers and SATA 3.0 Gbit/s devices was important, so SATA/300's autonegotiation sequence is designed to fallback to SATA/150 speed (1.5 Gbit/s rate) when in communication with such devices. In practice, some older SATA controllers do not properly implement SATA speed negotiation. Affected systems require user-intervention to manually set the SATA 3.0 Gbit/s peripherals to 1.5 Gbit/s mode, generally through the use of a jumper.[2] Known faulty chipsets include the VIA VT8237 and VT8237R south bridges, and the VIA VT6420 and VT6421L standalone SATA controllers.[3] SiS's 760 and 964 chipsets also initially exhibited this problem, though it can be rectified with an updated SATA controller ROM." So, as far as I can see, it'll just offer a speed increase (where possible). If your find your drive won't work when jumpered that way, I'd expect that you could put the jumper back on and go back to running at half speed. -- [tim@bigblack ~]$ uname -ipr 2.6.23.1-10.fc7 i686 i386 Using FC 4, 5, 6 & 7, plus CentOS 5. Today, it's FC7. Don't send private replies to my address, the mailbox is ignored. I read messages from the public lists.
