Hard Drive question - sata vs sata 3

[spankmon]

If my understanding is correct, mechanical harddrives cannot approach transfer speeds of even 3 gb/s.... so it seems useless to purchase a sata3 HDD when a sata drive will be just as fast. I found some recertified sata WD 3gb/s 750GB 32mb cache drives with 90 day warranty on newegg.com for $100 and this sounds like a fair price (at the moment, considering new prices). Please tell me whether it would be a better idea to buy one of these, or a new sata 6 gb/s 500GB drive for $130 US. Am I mistaken about the difference in read/write speeds? Thanks.

PS: The drive will be going into a new Sandy Bridge build, MOBO has both sata and sata3 connectors.

 

[WyomingKnott]

The real reason that HDDs come with SATA III interfaces is that it is cheaper and more efficient to manufacture and warehouse only one chipset. So instead of putting SATA II interfaces on HDDs that can't take full use of the SATA II interface, it makes economic sense to put SATA III interfaces on them. They certainly don't do any harm.

 

[Guest]

HDD R/W speed is completely different from there interface speed,so it's completely wrong to consider that a 3 or 6 Gbps interface HDD deliver that speed.As I know It's the maximum and possible data transfer rate of interface(simply a standard) between logic units and memory units.

But it's obvious that SATA III or a 6 gbps HDD provides better performance,data rate and access speed.

 

[WyomingKnott]

...
But it's obvious that SATA III or a 6 gbps HDD provides better performance,data rate and access speed.

I don't think so. Access speed in HDDs is dominated by head-movement and platter-rotation speeds; putting a bigger pipe between the drive and the CPU won't make any difference at all. Data rate - maybe, in bursts, if the HDD has a cache. When the data is being read from the cache, you could get a burst over the max physical read rate of the drive. But unless you are reading the same 32 MB over and over again, this will have a negligible impact.

 

[Paperdoc]

OP, you're on the right track. For mechanical HDD's there is NO performance difference between SATA 6 Gb/s and SATA 3 Gb/s units, so there's no need to pay for the higher spec. However, your real issue is whether or not you feel the re-certified units are as reliable as brand new ones, and whether any possible risk with them is worth saving that money involved. Personally I'm inclined to think that WD knows what they are doing and can do good repairs on HDD units before re-certifying. However, I have NO direct experience on this. Maybe others can offer real knowledge.

 

[spankmon]

Thanks for the replies.

I think I'll buy one of the recertified drives and use it for non-critical storage for a few months. Once my confidence in the unit is established, I'll use it just as I would a new drive. But probably will keep backups of the most important stuff anyway. If it continues to function for more than a few years, then I'll consider it money well spent. Thanks again.

 

[spankmon]

Best answer selected by spankmon.