07-01-2011 08:27 AM
I purchased three ST1500DL003 drives from the same vendor at the same time. All drives show firmware CC32. Only one of them is showing the sustained transfer rate that I expect.
I have tried swapping SATA cables and motherboard ports, and the behavior tracks the drive, therefore this is not an issue of SATA cables or the SATA port it is attached to. I also tried using the CC32 firmware update, but it said they are already the latest version and would not be changed.
Here are HD Tach results for the three drives:
You can see that one of the drives peaks well over 140MB/s, while the other two peak at less than 130MB/s. The drive is specified at 144MB/s sustained transfer.
Are the slower drives defective? If they are not, how can I get them to be as fast as the other one, and meet specification?
07-01-2011 04:49 PM - edited 07-01-2011 04:53 PM
A drive always tails off towards the end of the tests.
Yours drops to 60, my 3TB drops to 80, but the 3TB is a 7200rpm unit, yours is 5900rpm.
07-01-2011 06:10 PM
I am well aware of the falling speed curve of HDDs from outer to inner tracks. The point is that two of the drives are not as fast as the other one, and that these are well below spec. Please look at the charts again.
07-02-2011 12:22 AM
07-02-2011 09:09 AM - edited 07-02-2011 09:51 AM
fzabkar, that is an interesting possibility. I have a limited window for returning these, so I will have to limit the analysis I do; I don't think I'll try the RS232 thing. Later I can try weighing the drives.
I believe that "9VT16L" is an extended model number, not a serial number. At least that is the way it is reported by software utilities. The actual serial numbers are an eight character alphanumeric. The fast drive and one of the slow ones' differ by only the last two characters; the second slow drive differs in the last four.
You raise an interesting question: how do the 1.5TB drives differ from the 2TB drives? An unpleasant possibility comes to mind: if these are short-stroked 2TB drives, perhaps these are 2TB drives that had physical defects on the outer or inner edge of the platters, and they set a 1.5TB range to avoid these. If the drive is short-stroked toward the outside then it is faster; if toward the inside it is slower. If this is the case, then the slow drives are defective by design, and their STR spec is a lie, and this is unacceptable. I really hope this is not the case, but it would explain why the 1.5TB model exists and is priced less than the 2TB model, if they are physically identical.
(I am attaching a more precise STR chart from a full surface scan of the drives.)
07-02-2011 03:04 PM
07-02-2011 05:27 PM - edited 07-02-2011 07:34 PM
Yes, the serial numbers begin 5YD. What is the purpose of keeping these secret anyway? I would have included them but I observed that they were removed from other posts by a moderator.
Thank you for your help with this. You know that 17 zones must be across the full width of the platter? It cannot be over a restricted portion of a platter?
I shall read through the material you referenced, but for pragmatic summary:
Do any of the scenarios you propose allow for the slow drives to be made faster?
If not, would you agree with the statement that these drives are below spec and therefore defective?
07-02-2011 08:24 PM
08-11-2011 03:04 AM
08-11-2011 04:12 PM - edited 08-11-2011 04:13 PM
If the two new drives are doing the same as the old this suggests either a driver or a bios issue with your motherboard.
Latest chipset drivers especially the USB ones.
Latest bios and flash it
Check MB maker site for known issues
If you are on Intel, get the RST driver as well.
Knowing what you are using them with would help as well.