HD Diags, Benchmarks, Warranty, and Other Important Info
Updated 10-01-2006
Manufacturer's Diagnostics
ANY TIME a hard drive is in question as to a problem, run the manufacturer's diagnostics!
People need to be aware of the fact that NO non-brand specific program can do as good of a job as the manufacturer's own diagnostics because contrary to what many believe, SMART data is NOT standardized among all brands, nor are the threshold values that trigger a SMART alert. It is still commonplace for SMART errors to pop up, yet the manufacturer's own diags report no problem. ANYTIME a SMART error occurs, run the manufacturer's diagnostics to confirm or deny that there is a problem. Then use whatever program one wishes in an effort to recover from it. In ALL cases, when the manufacturer's diagnostics report bad sectors, it is a very wise decision to wipe/erase/zero/LL format the drive, then re-run all of the tests to see if any bad sectors remain. If some remain then consider the drive toast.
Note: the above is not an all-inclusive list. It is what we recommend and use in view of our purposes, explained shortly.
ATTO Configuration
Comparisons of ATTO benchmark results are not necessarily valid unless users adhere to the following ATTO setup options. Click image for full size.
A Few Words About Benchmarks
The primary, and some (including myself) will argue, only valid use of HD benchmarks in a setting such as this forum, is for troubleshooting performance related issues. We're not writing reviews here. When the norms of a drive's performance using these benchmarks are known, then the tools and methods used here are valid. They tell us what we need to know to answer the question "is this okay?" In no way do any of these benchmarks prove or disprove that the mass storage subsystem is optomised for the purposes of the user. There is a lot more to drive performance than benchmark results and sequential read/write speeds do not tell the whole story. More words of wisdom HERE.
Hard Drive Manufacturer Warranties
The following are links to the current warranty periods and policies of hard disk drive manufacturers. Note that retail, reseller, and OEM warranties may be different. Check with your vendor for their policies. I update/verify these links at least once a month.
Western Digital SATA drives have a jumper block next to the 4 pin molex power connector. Click the image for full size.
This jumper block sets the drive's power management mode. The default position is the jumper on pins 1-2 (PM disabled). Removing the jumper has the same result. Jumpering pins 3-4 (PM enabled), causes the drive to power-up in standby mode. In most cases the default jumper position should not be changed. Note: there are no master/slave relationships using SATA drives. Reference here.
WD PATA Jumper Setup
By far the most common problem WD owners/users run into is caused by incorrect jumper settings. WD is different. Refer to the following. Note that all current PATA models have a 10 pin jumper block. Click the image for full size.
The best rule of thumb is to remove the jumper from the drive when it is the only drive on the cable. Either of the "single" settings is functionally equal to removing the jumper.
Hard Drive Capacities
HD manufacturers specify drive capacity in decimal. Windoze displays it in binary.
Decimal capacity / 1,048,576 = Binary MB capacity
Example:
A 40 GB drive is approximately 40,000,000,000 bytes (40 x 1,000,000,000).
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Re: HD Diags, Benchmarks, Warranty, and Other Important Info
Location of internal temperature sensor on WD PATA and SATA drives. External sensors, if used, should be attached on the drive case as shown in the following picture. Click for full size image.
Re: HD Diags, Benchmarks, Warranty, and Other Important Info
For those using non-WD specific utilities to monitor the SMART status of WD drives, beware. These are the attributes capable of being monitored and reported. Other attributes displayed/reported by non-WD utilities should be ignored.
Re: HD Diags, Benchmarks, Warranty, and Other Important Info
I have recieved a number of requests for info regarding Western Digital's own serial ATA PCI controller card, model WDAD10. It is in fact a Promise S150 TX2 Plus without the ATA133 PATA port. The controller chip is a Promise PDC20371. Neither TCQ or NCQ are supported.
Promise PCI cards that DO support TCQ and/or NCQ are:
Re: HD Diags, Benchmarks, Warranty, and Other Important Info
I have been getting a lot of queries regarding NCQ (native command queuing) and TCQ (tagged command queuing). They are not the same thing.
Here is WD's explanation of the difference between the two.
Quote:
Definition of Native Command Queuing (NCQ)
* Native Command Queuing allows multiple commands to be outstanding within a drive at the same time. Hard drives that support NCQ have an internal queue where outstanding commands can be dynamically rescheduled or re-ordered, along with the necessary tracking mechanisms for outstanding and completed portions of the workload. NCQ also has a mechanism that allows the host to issue additional commands to the drive while the drive is seeking data for another command.
* NCQ allows the drive to set up the direct memory access (DMA) operation for a data transfer without host software intervention. This is also called first-party DMA - it means that the device is capable of complex sequences of operations without CPU intervention. The drive itself knows the current angular and rotational position of the drive head. The drive then selects the next data transfer to minimize both seek and rotational latencies.
Definition of Tagged Command Queuing (TCQ)
* Tagged Command Queuing is a standard as a way to allow hard drives to accept multiple concurrent commands from a host PC. When commands arrive at the drive's buffer, they are tagged with an identifier and then reordered by the drive’s microprocessor to minimize the distance the drive's read head needs to move laterally along the platter looking for data. For example, if a command is looking for data in one section of the drive and a following queued command is looking for data in a neighboring area, the host adapter can reorder the commands to make the two occur sequentially. This is a different system than IDE/ATA, which will allow only a single command to be outstanding at a time to any device and processes requests serially.
The articles section at The Tech Report contain several reviews and comparisons of drives, and the effects of command queuing, and the conditions under which they were observed.
In summary, for most people, and at this time, neither queuing method offers much of a real-world advantage in a typical home PC.
A couple new WD Support items specific to SATA-II models:
Quote:
Problems are encountered when installing Second Generation Serial ATA hard drives on VIA chipset Serial ATA controllers.
Question
Why is my Second Generation Serial ATA hard drive not detected by my VIA Serial ATA controller or motherboard?
Problem:
Second Generation Serial ATA hard drives are not detected when connected to a VIA Serial ATA controller. These controllers include the following chipsets:
VT8237
VT8237R
VT6420
VT6421L
Cause:
WD Second Generation Serial ATA hard drives use autospeed negotiation. This enables our Second Generation Serial ATA hard drives to automatically detect the motherboard data transfer rate, making it backward compatible with First Generation Serial ATA data transfer rates. However, because this technology is so new, some older motherboards are unable to support autospeed negotiation and cannot recognize the drive. This “drive not detected” condition occurs when a chipset is incapable of correctly negotiating the data transfer speed with a Second Generation Serial ATA hard drive.
Please refer to the following WD information page for a fix:
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