Any caveats to using a 2.5" HDD in a desktop?

[Unknown-One]

I ended up replacing the hard disk in my bedroom media center PC with a spare 2.5" hard disk (Seagate, 320GB, 7200RPM) that I had lying around. This lead to a pretty substantial decrease in heat and noise output from the machine, to the point that I was able to remove the small PC's only intake fan without a rise in temperatures. Performance is slightly better than the old 3.5" drive as well.

Cooler, quieter, fast... first thing that came to my mind was "why isn't everyone using these instead of 3.5" drives?"

I've since considered replacing the drives in some of my other PCs with 2.5" disks to quiet them down, but that question keeps nagging at the back of my mind. Despite all the advantages I'm experiencing, why aren't these 2.5" drives more popular in desktops? If I do replace a few of my desktop drives with them, is there anything I should look out for?

 

[drescherjm]

Current generation laptop hard drives are significantly slower than current generation desktop drives even when you compare 7200 RPM ones to 5400 RPM desktop drives. If you are happy with the performance of a laptop drive then go for it..

 

[Old Hippie]

Performance is slightly better than the old 3.5" drive as well.

And that drive was..........?

 

[jiminator]

2.5" drives are optimized to minimize heat output and energy requirements. That means they will run slower and possibly have less platters than a 3.5". The fact that your system is faster probably means that your last drive was cheap/bad/fragmented or you had a bad os install.

 

[ghost6303]

"why isn't everyone using these instead of 3.5" drives?"

-less platters mean more information is stored on the inside tracks of the disk. more platters means there is more space on the outside edge of the disk (where its the fastest) to store information.

-laptop drives are generally more expensive when you look at $ per GB.

-laptop hard drives are generally slower then an otherwise identical 3.5" HD

-my case doesnt have 2.5" drive bays.


however if you are going for either power savings, or for storage density (GB per unit of volume), or have another reason you cant use a 3.5" drive, then laptop hard drives are not a bad option. there is no hardware or software reason you couldnt use one.

 

[Unknown-One]

Current generation laptop hard drives[...]

Why does everyone automatically jump to "laptop hard disk" when they hear 2.5"? There are 2.5" drives that have no business being in a laptop

2.5" drives are optimized to minimize heat output and energy requirements. That means they will run slower and possibly have less platters than a 3.5".

Last time I checked, having a fewer number of smaller (high density) platters was better than having a large number of low density platters. The data is closer together, so more data passes under the heads with the same amount of rotation.

And like I said, not all 2.5" drives = laptop drives. Look at Western Digital Velociraptors, they're 2.5" and wicked fast (I know some people have gone ahead and installed them in laptops, but that's most certainly not their intended use).

The fact that your system is faster probably means that your last drive was cheap/bad/fragmented or you had a bad os install.

I imaged the old drive sector-by-sector to the new drive, so if there was anything wrong with the OS or file system it would have been copied right over. Everything appears to be operating normally (just faster) so I'm pretty sure everything is in order on that end.

And that drive was..........?

The old drive was a 3.5" Maxtor DiamondMax 10. HDTach scores it at 14.7ms seek, 56MB/s average read speed. Not great, but not bad for a drive from 2005.

For comparison, the 3.5" Western Digital Caviar Black 1TB hard disk in my desktop PC scores 12.2ms seek, 92MB/s average read.

The new 2.5" drive from Seagate scored 12.6ms seek, 75MB/s average read speed. Its seek time is as good as the WD Caviar Black without sounding like a freight train while seeking, and the read speed isn't too shabby either (especially if you compare it to 3.5" drives in the same price range as it).

 

[Old Hippie]

Look at Western Digital Velociraptors, they're 2.5" and wicked fast (I know some people have gone ahead and installed them in laptops, but that's most certainly not their intended use).

Those drives prove the rule about 2.5" drives because they're server/pro drives intended to compete with SAS drives and have too much height for 90% of the current laptops.

The old drive was a 3.5" Maxtor DiamondMax 10.

No doubt you're enjoying the upgrade.

The new 2.5" drive from Seagate scored 12.6ms seek, 75MB/s average read speed. Its seek time is as good as the WD Caviar Black without sounding like a freight train while seeking, and the read speed isn't too shabby either (especially if you compare it to 3.5" drives in the same price range as it).

Let's talk price/GB which has no meaning for me but I see it discussed alot.
Looks like that 2.5" drive you purchased is @ .38 per GB. while normal 3.5" drives are @ .10 per GB.

I'm glad you're satisfied but it doesn't seem very cost effective (or anything else) to me unless you're a noise "Natzi", and in that case SSDs will be your nirvana.

PSSS.....I'm definately not against 2.5" mechanical drives in a DT but the only advantages they have are noise and heat when compared to 3.5" drives. If you're willing to pay a premium for those aspects more power to ya but they're many alternatives that are superior.

 

[drescherjm]

Why does everyone automatically jump to "laptop hard disk" when they hear 2.5"? There are 2.5" drives that have no business being in a laptop

You were talking about cooler and quieter 2.5 inch drives. Velociraptors are neither cooler nor quieter than a typical current generation 3.5 inch drive. I have a few of these at work so I know. Also SAS drives are not cooler or quieter either.

I do not know of any other non laptop 2.5 inch drives than sas or velociraptors.

 

[Unknown-One]

Let's talk price/GB which has no meaning for me but I see it discussed alot.
Looks like that 2.5" drive you purchased is @ .38 per GB. while normal 3.5" drives are @ .10 per GB.

Seagate 2.5" 7200RPM 320GB = $55 at Amazon
Seagate 3.5" 7200RPM 320GB = $44 at Amazon

$11 isn't a big enough difference for me to care. [Edit] Heh, I googled some benchmarks of the 3.5" Seagate. It's actually marginally slower than the 2.5" drive across the board.

I'm glad you're satisfied but it doesn't seem very cost effective (or anything else) to me unless you're a noise "Natzi", and in that case SSDs will be your nirvana.

I mentioned in my first post that it's the boot drive for a bedroom media center PC, so being quiet is paramount. This drive is quieter than any 3.5" drive I can remember hearing, so that's a major plus point.

A 40GB SSD might have worked OK, but those are around $100 and I would worry about it getting cramped over time (even though it's just a dedicated media center). The performance would have gone to waste 99% of the time as well, so it was hardly worth it.

PSSS.....I'm definately not against 2.5" mechanical drives in a DT but the only advantages they have are noise and heat when compared to 3.5" drives. If you're willing to pay a premium for those aspects more power to ya but they're many alternatives that are superior.

Low noise and low heat (meaning fewer cooling fans) were paramount in this particular application, and I definitely got that with the 2.5" drive.

What I'm surprised with is the performance. That 12.6ms seek time makes it feel like the WD Caviar Black in general usage, and the sustained read/write speeds are quite good as well.

You were talking about cooler and quieter 2.5 inch drives. Velociraptors are neither cooler nor quieter than a typical current generation 3.5 inch drive.

It was an example, taken to the logical extreme for effect. The point being that there's nothing stopping 2.5" drives from performing well (which is good, because SPCR has found 2.5" drives to be inherently quieter than 3.5" drives)

 

[Old Hippie]

Rationalize all you want but your origional question has been answered.

 

[jiminator]

another aspect is that drives can do "sector remapping". That allow the drive controller to move data from defective sectors to other that are reserved explicitly for remapping. It is transparent to the OS although it may be visible in the SMART data. If you have a lot of remapped data the seek tries to access it will increase dramatically. Doing a sector by sector copy of the drive to a new one would fix the problem.

 

[Old Hippie]

another aspect is that drives can do "sector remapping". That allow the drive controller to move data from defective sectors to other that are reserved explicitly for remapping. It is transparent to the OS although it may be visible in the SMART data. If you have a lot of remapped data the seek tries to access it will increase dramatically. Doing a sector by sector copy of the drive to a new one would fix the problem.

Are you saying that only 2.5" drives do this?

If so, how 'bout a link?

 

[Unknown-One]

Rationalize all you want but your origional question has been answered.

The 2.5" drive is cooler, quieter, and marginally faster than its 3.5" counterpart. There's nothing to rationalize here, the 2.5" drive is simply better.

I'm still left wondering why these drives aren't used more in desktops...

Are you saying that only 2.5" drives do this?

He's saying that reallocated sectors might have been what was slowing down the original 3.5" drive. SMART reading is clean.