What does WD hard drive have, that Seagate Hard Drives dont?

Computer_Freak

Computer_Freak

Active Member
I see the price diff and I wonder...

Besides the Velociraptor, they have the same cache, same rpm.

What does Cache do on a HDD?

I guess RPM allows it to read faster...

so what makes them so much better to justify that price increase?
 
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This is from my experience so take this as you want. I have owned 8 Seagate harddrives in my life and 30 something western digitals. Out of the 8 seagate 4 of them died. Out of the 30 plus WD`s I have only had 2 die. Maybe it`s luck, but I doubt it. I used to work at a computer store and the only drive we used to build peoples systems with were WD`s.
 
so you're saying WD drives are more expensive or Seagate?
Typically WD drives are less expensive (if you look at 7200RPM drives) though usually not by much.

Could you post an example?
 
WD is more expensive (well here in south africa, i forget to check US prices...)

So you say they more reliable.

What does cache do on a HDD?
 
nvm, i got it

Hard drives are mechanical devices: no matter how much you improve the dynamics or increase the spindle speed, a mechanical transfer will always lose out (in terms of performance) to an electrical system. To alleviate/hide the slow nature of hard drives, they [the drives] are often equipped with a small amount of high-speed memory. When a request is received, the drive checks for a match in the cache before "manually" locating the data on the various platters: if there is a cache-hit (i.e., the data required is there) then the data can be immediately transferred thus eliminating seek times. Increasing the amount of cache available on the drive noticeably improves. Hard drives usually come with 2MB, 8MB or 16MB of cache. For some fancy RAID controllers, there is also cache memory present on the controller.



So its just reliability?
 
Computer_Freak said:
WD is more expensive (well here in south africa, i forget to check US prices...)

So you say they more reliable.

What does cache do on a HDD?
Click to expand...

"The function of cache is to act as a buffer between a relatively fast device and a relatively slow one. For hard disks, the cache is used to hold the results of recent reads from the disk, and also to "pre-fetch" information that is likely to be requested in the near future, for example, the sector or sectors immediately after the one just requested.

The use of cache improves performance of any hard disk, by reducing the number of physical accesses to the disk on repeated reads and allowing data to stream from the disk uninterrupted when the bus is busy. Most modern hard disks have between 512 KiB and 2 MiB of internal cache memory, although some high-performance SCSI drives have as much as 16 MiB, more than many whole PCs have!"
http://www.storagereview.com/map/lm.cgi/buffer
 
some have 32Mb...
Click to expand...
And all don't need 32MB....

The article is old but the principle of cache is the same. It doesn't matter if you have 1MB or 128MB of cache it still does the same job.
 
We looked at several Seagate Barracuda 7200.10 drives to get down to the performance nitty-gritty. In doing so, we found that there is hardly any difference between two drives that only differ in their cache sizes: 16 MB cache has no significant advantage over 8 MB across our benchmark suite, and this applies both to Serial ATA and to UltraATA drives. We would have expected that at least the SATA drives would show some degree of benefit, but in the case of the 7200.10 family, 16 MB cache is a waste of money if you have a cheaper 8 MB alternative. At the same time, 16 MB cache doesn't hurt either if the price is about the same...
Click to expand...
Because it isn't used. I'm not a big fan of Toms Hardware but not being able to find an article on StorageReview or something it's the best I've got http://www.tomshardware.com/reviews/understanding-hard-drive-performance,1557.html (the quote above is from the conclusion). Toms doesn't even try to explain why the cache doesn't make much difference. Maybe xbit...I'll edit this post if I find a good one.
 
Ford vs. Chevy. Both brands have sterling reputations for performance and reliability. There were issues with some of the Seagate 7200.11 drives in the larger capacities due to a firmware problem. I'm sure that's resolved now. I remember years ago when WD had a long run of defective drives. Overall it is Ford vs. Chevy.
 
I've had a Seagate and a WD die, though they performed well before that happened. Samsung Spinpoints are great, good price/capacity ratio.
 
Ive had Seagates and WD before and all the Seagates died and all the WD survived. Hitachi is pretty good to I have one now and its been going strong.
 
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