Late 2009 27" iMac SSD Speed Test

[eddjedi]

I've just put a 256GB SSD in place of the optical drive in my 2009 iMac. I'm impressed at how much better it performs and feels, it boots far quicker and there's noticeably less lag when opening apps and files. Copying large files is significantly faster. However I just ran a speed test with BlackMagic and am somewhat disappointed with the test results (see attachment.)

My stock 1TB internal HD gets read and write scores of about 100MB/s so the read and write of the SSD drive (especially read) are significantly quicker, so the upgrade certainly wasn't a waste of time. But they're nowhere near the 300MB/s+ the SSD is supposed to achieve.

So I was just wondering if this is to be expected. I realise that the optical drive connection is only SATA II, could this be to blame? Are manufacturer read/write speeds always so optimistic, or is the drive possibly faulty?

I'd be interested to know if anyone that's done the same upgrade could share their test results. Thanks.

 

[eddjedi]

I've just done a little digging and am slightly concerned after seeing this post:

https://forums.macrumors.com/threads/1280118/

They're using the same test app as I am. One guy is getting speeds near to my SSD from his 7200rpm HDD! I realise the conditions are different, but surely my SSD shouldn't be so slow?

 

[WesCole]

What brand/model of SSD do you have? Your speeds are much faster than my 1TB 7200 RPM drive in my 2011 iMac.

 

[eddjedi]

Thanks for the reply. I have a Lite-On 256GB SSD. Spec here:

http://www.liteonssd.com/25q-sata-mlc-ssd/item/root/25q-m2s-mlc.html

As you can see, should be getting well over double the read/write speed I am. It's not terrible or anything, significantly quicker than my HDD so performance is improved, but it's just not as fast as I was expecting so ideally would like to see what kind of speeds other people who have done the optical bay upgrade are getting.

 

[eddjedi]

Here are 2 more screenshots - the first is my internal 1TB HD, and the second is the built in SSD in my 2010 MacBook Air. In my opinion based on the claims of the drive manufacturer, the SSD I have put in my iMac should be significantly faster than both. Unless somebody can chime in and tell me it's just due to the optical drive SATA connection. Can anybody help?

 

[eddjedi]

I found this thread with a good suggestion:

https://forums.macrumors.com/threads/1371521/

Both my stock 1TB HD and the new SSD in the optical bay are reporting SATA 3GBPS (both link speed and negotiated.) I also installed TRIM enabler, no difference either.

So bearing in mind my iMac seems to have no problems with the SATA connections, is it possible the drive is faulty? Or is a 40% reduction in speed due to my iMac being SATA 3GBPS rather than 6GBPS likely?

 

[JasperNL]

I have similar results with my SSD drive on my iMac 2011. The SSD drive was installed by Apple (BTO). Was a little disappointed about the results too.

 

[mactmaster]

It's 3Gbps meaning around 300 MBps max bandwith but in real world usage the throughput is close to what you are seeing. This drive would likely be faster on a system with 6Gbps SATAIII.

 

[AdamJohnG]

I have a Crucial M500 240GB in the DVD enclosure and it has a Link Speed of 3 Gigabit. I enclose photos of the Black Magic Test and SATA Express device info.

All modern SATA SSD's are SATA III 6 Gigabit, most should work as SATA II 3 Gigabit but it seems that some will default to SATA I 1.5 Gigabit when SATA III does not work. I am not sure if there is a defined list of these drives. I would purchase the SSD from someone like Amazon, and if it will not negotiate at 3 Gigabit, return and try a different model.

Obviously not worthwhile paying high bucks as the very max you will get is less than 300 MB/s.

I would purchase a Crucial MX500 or similar through somewhere like Amazon and then if it does not do the 3 Gigabit link speed, return and try a different SSD

 

[mbosse]

Thanks for the reply. I have a Lite-On 256GB SSD. Spec here:

http://www.liteonssd.com/25q-sata-mlc-ssd/item/root/25q-m2s-mlc.html

As you can see, should be getting well over double the read/write speed I am. It's not terrible or anything, significantly quicker than my HDD so performance is improved, but it's just not as fast as I was expecting so ideally would like to see what kind of speeds other people who have done the optical bay upgrade are getting.

The SATA ports in your iMac are limited to SATA II 3 Gigabit, while your SSD would achieve SATA III 6 Gigabit - it is limited by the SATA ports of your iMac.

Nothing is wrong here, everything works as expected in this combination.

Magnus

 

[tyc0746]

I would purchase a Crucial MX500 or similar through somewhere like Amazon and then if it does not do the 3 Gigabit link speed, return and try a different SSD

Don't know why anyone is posting in an 8 year old thread, but the OP might have an issue in trying to return a SSD after 8 years!