replace SSD drive with HDD on MBA

[sjivan]

Hi,
I recently bought a MBA with the 128GB SSD. When at the store I launched Word on the SSD version as well as the SATA version and there was a noticeable difference so I decided to pay the extra $700 and go with the 1.86GHz with SSD model.

I use this machine for development and my builds carry out file intensive operations that delete and generate a few thousand files (when I generate javadocs). My old Dell desktop from 5 years ago completed this operation in 90 seconds but my MBA takes 400 - 700 seconds which is really frustrating.

I did some reading and all indicators seem to point to the SSD being fast for reads but slow for writes. Is this correct? I'm not sure I can deal with this slowdown for much longer and I'm thinking a having my SSD replaced with the SATA drive. This should help, right? Will the mac store do this? or is there any less expensive option?

Thanks,
Sanjiv

 

[Coyote24]

SSD vs SATA

Good day,

... My first post here!

*disclaimer*I do not have a MBA at this time.

But:
I am thinking of getting an MBA. For me if I get a laptop it is because of the portability; period.
I have to aknowledge from the start that I will not have the crunching power of a Power Mac G4 with an MBA.
Everything else between PoweerMac and MBA is a compromise between portability and power.
If I did not have a home base MAC I do not think the MBA would be my first choice.
Given these parametres I still want to get the best experience with the MBA.
So, SSD or HDD? SSD, I will even say the smaller SSD avaialble please.

Why, well the speed difference is not gonna be great between the two drive and the HDD is only 5500rpm (or is it even that fast?)or so from the start ... so forget performance there.
Why the smaller unit? Well even 200G is not a lot so forget about using your MBA as a storing device at all, transfer your work regularly, access it via MobileMe or some Http service.

Now, with the situation you described above (and this is what I want to test) I would like to test the MBA connected via USB or wireless to an extenal fast HD on my home network. I am convinced that with that we would have decent results and all the MB/Gb/TerraB we want.
Any one want to test my theory?
I am thinking a fast external drive (say 10,000rpm) with a large buffer to compensate somehow for the USB connection.

- USB 2.0 has a raw data rate at 480Mbps (naturally FireWire would be better with transfer rate of some 1.5GB per second but hey...)-.

Finally why an SSD in the MBA? Well write on SSD is not 'fast' but read is! SSD has no mechanical parts and for me in a portable that is huge advantage. Then there is less heat and a slightly lighter electrical consumption.

At the end of the day I do not think I would debug a JAVA script do some heavy photo editing on the MBA or on any Laptop for that matter, but you can code on it, present with it etc!
And then transfer your wrk on your G4 or whatever you have when you get home and start crunching then.
You could sit on the couch with your MBA and send your work to your base station/ external drive wirelessly for processing.

Now a teaser: installing similar drive on your network...
http://www.hyperossystems.co.uk/

thx.
Alain

 

[aleksandra.]

Hi,
I recently bought a MBA with the 128GB SSD. When at the store I launched Word on the SSD version as well as the SATA version and there was a noticeable difference so I decided to pay the extra $700 and go with the 1.86GHz with SSD model.

I use this machine for development and my builds carry out file intensive operations that delete and generate a few thousand files (when I generate javadocs). My old Dell desktop from 5 years ago completed this operation in 90 seconds but my MBA takes 400 - 700 seconds which is really frustrating.

I did some reading and all indicators seem to point to the SSD being fast for reads but slow for writes. Is this correct? I'm not sure I can deal with this slowdown for much longer and I'm thinking a having my SSD replaced with the SATA drive. This should help, right? Will the mac store do this? or is there any less expensive option?

Thanks,
Sanjiv

SSD in rev B * is * a SATA drive.

SSD refers to the type of memory, while SATA is a connector. So, last revision MBA had either a PATA HDD or a PATA SSD, while current one has either a SATA HDD or a SATA SSD. You don't really get to choose between SATA and SSD, unless you mean refurbished rev A with SSD or current low-end model.

About SSDs in general: it's true that write on SSD is usually much slower than read on SSD. But good SSDs (and Apple uses good, though not the best) are faster than most hard disks in both reads and writes. And much, much better than 4200rpm HDD used in Air. Don't even think of downgrading if you want more speed.

 

[sjivan]

aleksandra,
Sorry if I confused the terminology. I got a brand new Air 1.5 months ago.

See http://store.apple.com/us/browse/home/shop_mac/family/macbook_air

I got the standard configuration 1.86GHz model. So yes, I was referring to downgrading to a HDD. So while I'm not sure how fast things will run / and my file intensive write operations will take on a HDD but I was guessing a lot faster given that my crappy dell runs the build so fast.

And to your point about good SSD's boing faster that HDD's even for writes, thats good to know but I dont know if that is something that can be done with Air. I called the apple guys and they said that the disk in Air cannot be changed (by them)

So should I just deal with having some of the write operations perform really slow, or try other options like swapping the disk?

Thanks,
Sanjiv

 

[glitch44]

So should I just deal with having some of the write operations perform really slow, or try other options like swapping the disk?

Thanks,
Sanjiv

There are currently no options for disk swapping. The Air takes a 1.8" drive that is no more than 5mm thick and has a SATA-LIF connector (which, apparently, is very rare/ possibly proprietary).

If you're looking for a number crunching machine, I'm afraid the Air isn't for you. Perhaps a unibody Macbook with 4 GB of RAM would crunch faster? Only 1 LB heavier...

 

[sjivan]

There are currently no options for disk swapping. The Air takes a 1.8" drive that is no more than 5mm thick and has a SATA-LIF connector (which, apparently, is very rare/ possibly proprietary).

If you're looking for a number crunching machine, I'm afraid the Air isn't for you. Perhaps a unibody Macbook with 4 GB of RAM would crunch faster? Only 1 LB heavier...

I'm holding out for the new Mac Pro's and I'm using the Air in the mean while. I understand that Air isn't a number crunching machine, however for my particular dev needs it appears like the bottleneck is not the CPU or memory, but rather the SSD which might not have been an issue had I gone with the HDD. So I feel a little disappointed that I spent $500 more on a laptop when a lower model would have done the job better for me.

Sanjiv

 

[Kan-O-Z]

I did some reading and all indicators seem to point to the SSD being fast for reads but slow for writes. Is this correct? I'm not sure I can deal with this slowdown for much longer and I'm thinking a having my SSD replaced with the SATA drive. This should help, right? Will the mac store do this? or is there any less expensive option?

Thanks,
Sanjiv

It is true that writes are slower than reads on SDDs. It may also be true that writes on the MBA SDD might be slower than the writes of a STANDARD 3.5" HDD such as the one in your Dell. The problem is that the HDD drive in the MBA is a very slow HDD(1.8" 4200 RPM). As a matter of fact, this drive is slower than a standard laptop HDD(2.5" 5400RPM). A standard laptop drive is slower than a desktop HDD(3.5" 7200RPM).

Even though your Dell is 5 years old, HDD technology has not advanced that much in terms of speed.

So to answer your question, you will probably gain nothing switching to a 1.8" HDD on the MBA since that is a very slow drive. It won't be any faster at writes than the SSD....and we all know it will be a lot slower at reads than the SSD.

What I would do if I were you is wait for a few months. There are newer, faster, cheaper SSDs that are coming out soon. There will be one soon that will beat your Dell, it's just a matter of time. Wait for that and then get someone to put in the new drive. There are electronics shops or computer repair shops around that work on Apple computer that will do this for you. You may even try to do this yourself at that time if you feel inclined. Some people on this forum have opened up their MBAs and have posted info here.

Kan-O-Z

 

[Scottsdale]

But, the other person said you wanted to downgrade to a v1 MBA, that is not the case. Whatever you do, do NOT downgrade to a v1 MBA... that would be ridiculous. The first version used PATA which is MUCH MUCH slower than SATA.

You just want to downgrade the SATA-II SSD to a SATA-II HDD. I don't think that is the issue here. The SSD has much faster read speeds than a HDD, but the write speeds are slower on the SSD than read speeds... however, the SSD should still write as fast or faster than a HDD. Yes, you can buy a HDD and put it right in your MBA. I don't think you really want to do that though. You need the right connector - something like an LIF to SATA-II. Debate on how to do it. I would imagine you could send your MBA to Apple for a change to a HDD, but again I don't think that is the issue.

Your problem is something else. The v2 MBA has an Intel Core 2 Duo Penryn 45 NM CPU. At 1.86 GHz, it's FAST! The CPU also has 6 MB L2 Cache - that is high quality too. The SSD is probably not the problem unless you have problems opening or using the SSD with programs and etc.

I cannot see anyway that a five year old Dell would outperform a brand new MBA 1.86 GHz Core 2 Duo, 6 MB L2 Cache, and 2 GB RAM running at 1066 MHz. Something has to be wrong. I don't know what is wrong, but something has to be wrong.

Before concluding it's your SSD, I think you need to research alternative problem possibilities.

Sorry could not help further. Best wishes with your new MBA. Great computer!

 

[sjivan]

The problem is that the HDD drive in the MBA is a very slow HDD(1.8" 4200 RPM). As a matter of fact, this drive is slower than a standard laptop HDD(2.5" 5400RPM). A standard laptop drive is slower than a desktop HDD(3.5" 7200RPM).

...

So to answer your question, you will probably gain nothing switching to a 1.8" HDD on the MBA since that is a very slow drive. It won't be any faster at writes than the SSD....and we all know it will be a lot slower at reads than the SSD.

Kan-O-Z

That's exactly the information I was unaware of and looking for. Thanks a bunch. So I get it now : Air SSD is slow for writes, but the Air HDD is no better and its not the same in terms of speed compared to the hard disk in my desktop.

I feel much better now.

Thanks!
Sanjiv

 

[freelancier]

sell it!

I don't know if other people have said that already.

If you just bought a new MBA RevB and it's not fitting your particular needs, sell it and get a different one...why bother paying more to downgrade it?

you can easily sell it for 50 bucks or less depending on how good you are at selling stuff!

If you downgrade it, you likely have to pay more with labor and parts lost, it makes no sense at all!

sell it for 2200 or even 2300, plenty of people will pay that price..
then buy the cheaper model and you still ended up saying a few hundred...