250GB vs 320GB - Hitachi 5k500.b

I'm looking at a getting a new hard drive and the price of the 250GB and 320Gb drives look ideal for me. Seeing as they are similar priced, I'm curious whether the 250GB will perform better and use less power.

As far as I can tell the 320GB drive is 2 platter so must use 160GB platters, whereas the 250Gb drive uses a single higher density drive.

Has anyone got any experience of the actually difference? Other advice?

Thanks

 

If you don't need the extra space get the 250GB version.

Theoretically it should be quieter and use less power because it's only one platter that needs to be spinned.

If the differences will be significant in real life, I'm not sure.

PS. the data density will be the same. The 320 model will probably have 250GB on the first platter and 70GB on the second platter.

 

Yes the 250gb drive will be quieter and more power efficient, but I suspect the 320gb 5K500.B will be the fastest of the series.

The 5K500.B is based on 250gb platters, so that means 125gb per side of the platter.
In order to make 320gb, that requires 3 sides. That makes 375GB.
Now they sell it as 320gb, so they limit the head movement to use the outer part of the platters.
The outer part of the platters are the fastest part of them, due to centripetal acceleration and the fact that the farther the head is away from the center of the drive, the more data can be kept there.
By only using the outer 320gb of the 375gb capacity, or outer 106.66gb of the 125gb platters, you dont use the slowest part of the drive, which happens to be the inside part of the drive. As a result the minimum drive speed should be much higher than a standard 500gb drive which uses the entire platter. Thus in a hdtune run, the benchmark will be more flattened and yield a higher minimum bandwidth.

The 320gb model should be the fastest capacity 5K500.B out there. However I have not found any benchmarks to back my ideas up.
I recommended it to a guy here but I havent PM'ed him in a while. If he has a benchmark I will have him post it

K-TRON

 

K-Tron is most likely accurate in his assessment about the 320GB version of the 500GB series as it is short stroked by the manufacturer to only use the faster portions of the platters. However, maximum speed and access time will almost certainly be identical between the 320GB, 250GB, and 500GB models.

If you are concerned about energy efficiency, heat, a few grams of weight, and/or noise the 250GB model may be a better choice (although the difference will be quite small), assuming it is a single platter design. If you think you might want the capacity, I would opt for the 320GB version as the performance may be slightly greater and the efficiency penalty is small.

 

Thanks again, I think I'll go for the 320GB as even if the performance is the same, the extra power consumption is negligible. I was just worried about a performance loss, which seems somewhat unlikely now.

I hadn't really considered it not using all of the platter so assumed it had a different platter size. Reading 3 sides makes sense as the drive has 3 heads according to the spec sheet.

Once it eventually arrives and I've got it set up, I'll post up some benchmarks to see if K-Tron's theory is right, assuming someone else doesn't beat me to it.

 

Good luck for your purchase.

 

Having finally received the drive, I've stuck Win7 64bit on it and run some benchmarks, which show the drive to be uniformly about 20% slower in all aspects (save seek) compared to the 500Gb 5k500.b. However, I need to stick it in my desktop and benchmark it there when I get round to it.

I've seen a few reports of people experiencing a 20% or so difference in HDD speed between windows 7 and Vista, which could account for the difference, and people are supposing it is due to the drivers not yet being optimised.

 

Ok, having tested the drive in my XP desktop, I can confirm it is definably slower than the 500GB version, though I have no 250GB version benchmarks to compare it with.

All these are carried out on my XP SP3 32bit (upgrading soon ), Q6600, 4Gb ram
I repeated the Hd tune and ATTO to see if the performance was vairable. It was actually impressively consistent.





Compared to the 500GB 5k500.b benchmarks I've seen, this is about 20% slower except access speeds as I found on Windows 7. It's a bit disappointing, but all in all not going to make any difference in usage.

Can anyone with this drive comment whether their drive performs the same.

 

How did you reach that conclusion?

 

When compared to any benchmarks of the 500GB drive, for example http://forum.notebookreview.com/showpost.php?p=4783646&postcount=34 there is clearly a marked difference.

 

The access time seems quite high, even for a 5400RPM drive.

 

I would not make conclusions like that based on a synthetic benchmark. Especially not if the synthetic benchmarks are conducted on different systems with different settings.

I don't see any reason that a 320GB version would really be 20% slower than the 500GB version. In my opion, these HDTune results certainly don't prove it.

 

Fair enough. It's not proof.

But 20% is a big difference and I get the same results in my windows 7 laptop, so perhaps there's some optimisation going on that I don't know about.

As for the 320GB being slower, I definitely didn't expect this given the same platter density and model. Perhaps the 320GB model uses the inside rather than outside edge, or it makes use of platters with too many bad sectors to qualify as full 250GB platters.

 

That could be true yeah.

If you would want to get more certainty about the performance difference you could run PC Mark Vantage.

Tomshardware has published the Vantage results for the 500GB 5K500.b.
http://www.tomshardware.com/charts/2009-2.5-mobile-hard-drive-charts/benchmarks,53.html

While Vantage is still synthetic, it uses traces of real applications.

 

PCmark vantage gets 2992 with my 320Gb drive vs 3527 for the Tomshardware 500GB.

 

And that's running Vista with advanced hard drive performance enabled?

If so, that would confirm that your drive is slower than the 500GB.

 

This is quite odd, I do not understand how this drive is underperforming.
There is no way, at least to my knowledge, to decrease capacity using the same density platters, without limiting the head movement.

With my analysis, your hdtune results should have had less of a camber in the results, but clearly that did not happen.

Is your drive set to SATA II for performance.
Have you run Hitachi Tool, to check the system drive speeds. It may be stuck in SATA I mode


EDIT:
Maybe the limited head movement is on the exterior of the drive?

Your drive peaks around 73mb/sec, while other users with the 500gb model peak at 85mb/sec
Maybe they are making 320gb out of the inner part of the drive and disregarding the outer part of the discs.
That would make sense for why yours is slower.
However I am not sure why Hitachi would do that

K-TRON

 

Perhaps some of the outer tracks of a platter are defective? I wonder if there will also be other 320GB HDDs with above-normal performance because the inner tracks are defective.

John

 

There have been HDTune benchmarks posted of 250GB Seagate 7200.3 that were faster than the 320GB versions.

 

It is in SATA II mode

This what I thought, however the decreased minimum (33.5 vs 38) is inexplicable. For the same design the lowest read speeds should be the same or higher no matter which area is being read from.

EDIT- I've found some interesting information in the OEM datasheets.



This suggests a lower track density for the 320GB drive, which corresponds to the different I've been seeing. This also implies the performance for the 5k500.b drives should go as follows:
500GB=250GB>120GB>320GB>400GB>160GB (and all benchmarks I have found confirm this)
I'm still curious how they manage to lower the track density though. Perhaps by skipping bad sectors as I supposed earlier?

 

I was also looking at the datasheet, but the one at Hitachi. However, while this shows number of heads and number and disks, it just shows a maximum data density for the whole range. The numbers you found don't conflict with the Hitachi datasheet but suggest that Hitachi set up each size of drive separately in order to spread the data out over the whole surface.

John

 

The datasheet I was referring to is also a Hitachi one. http://www.hitachigst.com/tech/techlib.nsf/products/Travelstar_5K500.B
It is the one labelled OEM specification (rather than being an datasheet produced by an OEM as I implied)