Eugene, on Sep 20 2006, 05:19 PM, said:
Seagate's latest is the first SCSI drive to incorporate perpendicular recording technology and pushes the bar for 15K RPM spindle speeds to an impressive 300 GB. How does the industry giant's newest fare? Join SR as we put the 15K.5 to the test!
Seagate Cheetah 15K.5 Review
A few comments.
The "lowest real-time price (300 GB)" link at the top of the article points to quotes for the 146 GB part.
The jpeg of a 15K.5 disk on the first page shows a ST3300655LW model (300 GB Ultra 320, 68 pin model I presume). The firmware revision is on the label but is too small to make out. Could you tell us which the firmware revision was used for the tests?
The lack of an effective desktop mode is puzzling. The PM (performance mode) bit has been in the Seagate vendor specific (unit attention) mode page for some time and is used by many models prior to the 15K.5 . It is also present in the 15K.5 and is changeable but seems to have no measurable effect. There is another "standard" (see SBC-2 and SBC-3) bit in the caching mode page called Initiator Control (IC) whose description is similar to the Seagate's for the PM bit. Could you set the IC bit in the caching mode page and see if it makes any difference for the single user performance tests? One would expect to see some benefit from the increase in cache size from 8 MB to 16 MB between the 15K.4 and 15K.5 series.
There are a few other improvements (over the 15K.4 series). The nonrecoverable read error rate has improved from 1 in 10**15 bits read to 1 in 10**16 bits read. Probably associated with this the number of ECC bytes per sector has increased from 54 to 68 bytes. Seagate's sales literature talks about "second generation" background media scan (BMS) support. The translation is that the 15K.4 series used a proprietary BMS scheme whereas the 15K.5 series complies with the BMS defined in SBC-3 (which is still a draft and can be found at www.t10.org ).
Sign In
Register
Help
MultiQuote
