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tbayrgs

macrumors 604
Original poster
Jul 5, 2009
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Just installed a brand new OWC Mercury Electra 6G into my early 2009 Mac Mini and while boot up seems quicker and app launching noticeably faster, I ran AJA System Test and the results were disappointing to say the least. I ran it multiple times with various configurations of Video Frame Size and File Size and consistently only received avg. write of about 106 MB/s and read of about 130 MB/s. I have my 2 HDD in my new 2011 Mini Server set up RAID 0 and I'm getting much better results than this with 7200 rpm HDD.

I realized this model of the Mini isn't going to be able to take full advantage of this model's capabilities as it's only SATA II vs. SATA III in new Minis (price was about the same as Mercury 3G models and this SSD may eventually make it into my new 2011 Mini) but these results seem quite low (200's MB/s maybe?).


System configuration: 2009 Mini 2.0 GHz C2D, 8 GB RAM, 120 GB OWC Mercuty Electra running OS X 10.6.8. I cloned the Mini's previous 320 GB 7200 rmp HDD to the SSD before its installation and other than the speed test results, everything else appears to functioning properly.

Any thoughts on what may be wrong, troubleshooting?
 
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Well additionally I think you have SATA II 1.5GBps instead of SATAII 3GBps.

In which case, your reported figures sound about right I think. You're saturating the bus. A good indication of bus saturation would be if you monitored the Disk I/O speed in Activity Monitor and noticed that it is a nice flat line pegged at the max speed, indicating that there is some bottleneck not related to the SSD.

I have an SSD on a 2009 13" MBP and it is also connected via SATA II 1.5Gbps. The SSD can go faster with the EFI 1.7 update but when I installed that I got all kinds of beachballing and hanging (this seemd to be a well known issue) so I left it at EFI 1.6 with the 1.5GBps connection, and I notice that my SSD also maxes out at about 130MB/s read.

Ruahrc
 
Well additionally I think you have SATA II 1.5GBps instead of SATAII 3GBps.

In which case, your reported figures sound about right I think. You're saturating the bus. A good indication of bus saturation would be if you monitored the Disk I/O speed in Activity Monitor and noticed that it is a nice flat line pegged at the max speed, indicating that there is some bottleneck not related to the SSD.

I have an SSD on a 2009 13" MBP and it is also connected via SATA II 1.5Gbps. The SSD can go faster with the EFI 1.7 update but when I installed that I got all kinds of beachballing and hanging (this seemd to be a well known issue) so I left it at EFI 1.6 with the 1.5GBps connection, and I notice that my SSD also maxes out at about 130MB/s read.

Ruahrc

Thanks for the info. I'm not home right now so I can't run another test until later but if I remember correctly, the graphical results in AJA were flat lines at max speed. Bummer, didnt realize this model only has 1.5 GBps and didn't think to run the test on my old HDD for comparison. Thanks again for the insight.
 
Well additionally I think you have SATA II 1.5GBps instead of SATAII 3GBps.

In which case, your reported figures sound about right I think. You're saturating the bus. A good indication of bus saturation would be if you monitored the Disk I/O speed in Activity Monitor and noticed that it is a nice flat line pegged at the max speed, indicating that there is some bottleneck not related to the SSD.

I have an SSD on a 2009 13" MBP and it is also connected via SATA II 1.5Gbps. The SSD can go faster with the EFI 1.7 update but when I installed that I got all kinds of beachballing and hanging (this seemd to be a well known issue) so I left it at EFI 1.6 with the 1.5GBps connection, and I notice that my SSD also maxes out at about 130MB/s read.

Ruahrc

Well is looks like you are partially correct. According to the System Profiler on my machine, the 2009 Mini uses the Nvidia MCP79 ACHI which supports link speeds of 3 GBps but my Negotiated Link Speed is only 1.5 GBps and thus, the reduced speed.

Any idea what may be causing the lower Negotiated Link Speed and can it be changed?
 
There is only a single figure that is important with SSD: those that concern themselves with the 4K blocksize read and write. The rest is in "normal use" meaning less.

Over 98% of disk activity concerns itself with these small blocks so that is where the gain comes from. If on the other hand you only use your computer with large files (e.g. audio or video editing) and do not use the majority of the time small block disk access then a SSD will not be a wortwhile investment. (it is the track-to-track seek and write, not the continous write and write that's important)

The other benefit of a SSD is that if value your data a lot AND if you get a reliable SSD (e.g. the Intel X25M G2 or the even more expensive commercial grade ones with SLC memory) then you will find that a SSD has a far higher life expectancy than a mechanical HDD. Drop a laptop with a running mechanical HDD and you might well damage the HDD and your data is gone, the SSD carries on. Similarly with power going off - the HDD is more likely not to have finished its writing due to the write lag.
 
Why not ask OWC about this? They should be able to look into it for you.

you are on the right track. my 2x esata hack a 2009 2.66c2d mini has 3gb and the 1.5gb comes and goes depending on the hdd/ssd in the mini. so the firmware of the drive seems to determine if it will play fast with a 2009 mini.. To the OP asking owc may help you. it could turn out that the 3g ssd will really go 3g in the 2009 mini and the 6g ssd is cut off at 1.5g in the mini. due to the ssd's firmware and how it plays with the minis firmware. you may want to return your ssd and ask for a 3g version.
 
Why not ask OWC about this? They should be able to look into it for you.

Good advice---did exactly that in an email to their support last night. We'll see what they have to say.
 
As I have two 09 Minis I'll be interested to read what you find out. I'm planning on upgrading them possibly next year so I may need to get OWC SATA II SSDs if the SATA III ones won't run at full speed.

I've got a SATA III SSD in my 2007 MacBook, but that's limited to SATA I anyway.

If you do need to get a 3G rather than a 6G SSD, do note that OWC does have a policy where they'll wave the restocking fee for returns on up to two of their 6G SSDs. See here for the full details of this policy: http://eshop.macsales.com/service/returnpolicy
 
Well, OWC tech support responded with pretty much exactly as expected--do a PRAM and SWC reset. Here's the email I received:

"It is possible that your Mac is simply addressing the drive wrong. However, there have been many Mac Mini and MacBook Pro models with SATA II bus types that will negotiate at only 1.5 regardless of drive installed. You can try and clear this up by doing the following PRAM and SMC resets recommended by Apple.

To reset the PRAM:
1. Shut down the computer.
2. Locate the following keys on the keyboard: Command, Option, P, and R. You will need to hold these keys down simultaneously in step 4.
3. Turn on the computer.
4. Press and hold the Command-Option-P-R keys. You must press this key combination before the gray screen appears.
5. Hold the keys down until the computer restarts and you hear the startup sound for the second time.
6. Release the keys and allow the computer to finish booting.

To reset the SMC, please follow Apple's guide for your model here:
http://support.apple.com/kb/ht3964

Sincerely,

OWC xxxxxx
Technical Customer Service Representative
Other World Computing, Inc. (OWC)"


I'm going to put my old HDD back in and see if it has the same reduced link speed and if so, going to forgo the SSD route as it's really not worth the expense as those reduced speeds.
 
Reinstalled the old 7200 rpm Seagate HDD and it achieves full 3 GBps link speeds so placed a call to OWC.

Per the rep I spoke with, it turns out that they are just encountering this problem with this specific model of Mini as well--problem is same as encountered with 2008 MacBook Pro 15" and 13" Macbook (all use same NVidia MCP79 AHCI for SATA) noted at the bottom of their product page.

They did advise me though that the Mercury Extreme Pro 3G will function at full SATA II speeds so the Electra is going back and I'll be trying the Extreme Pro 3G.

While certainly a bummer to have to go through this entire process, props to OWC as they owned up to the problem and were very helpful getting it resolved. Now just hoping that I don't see the same problem with the Extreme Pro 3G.
 
They did advise me though that the Mercury Extreme Pro 3G will function at full SATA II speeds so the Electra is going back and I'll be trying the Extreme Pro 3G.

While certainly a bummer to have to go through this entire process, props to OWC as they owned up to the problem and were very helpful getting it resolved. Now just hoping that I don't see the same problem with the Extreme Pro 3G.

Yes, I have a 2009 Mini with the OWC Mercury Extreme 3gb/s and it works just fine at the full 3gb/s. So, I think your swap will solve this problem for you and you'll notice a big difference in speed. I have enjoyed having the SSD.
 
Yes, I have a 2009 Mini with the OWC Mercury Extreme 3gb/s and it works just fine at the full 3gb/s. So, I think your swap will solve this problem for you and you'll notice a big difference in speed. I have enjoyed having the SSD.

Great to hear, thanks for the info.
 
this is owc's strong point. they are very good with bad gear. many companies are terrible. I had a feeling that it was the drive's firmware not agreeing with the mini's. I have put 25 different models of hdds/ssds into 2009 mini's 2.0 2.26 2.53 2.66. some do 1.5 some do 3.0 and the same model with different firmware can give different results. I am glad that owc is helping you.
 
Thanks for the info. Looks like I'll be buying 3G SSDs for my 09 Mac Minis when I get round to it. Hope the 3G SSD works well in your 09 Mini.
 
Just installed Mercury Extreme Pro 3G a few minutes ago and happy to report that Negotiated Link Speed is now 3 GBps and AJA System Test is showing write speeds of about 215 MB/s and read speeds at about 265 MB/s. Loving the new found speed.

Thanks again for everyone's input/advice/assistance.
 
Great! Think I better start saving for a couple of 3G SSDs (one for each of my 09 Minis).
 
Out of curiosity - outside of bench-testing, what type of file transfer reading/writing do you need to do that involves transfer rates of 6Gb/s?

I ask because I think the OWC 6G's are a little overkill for our needs. In real-world use I'd be surprised if any 6Gb/s SSD actually outperforms a typical Sata-II SSD for what you would typically use your Mac to do. Downloading, file transfers, movie ripping are all limited by internet connection speed, USB/Firewire speeds, and CPU power (respectively) - and all are slower than 6Gb/s.

I only bring this up because Sata-II SSDs are hundreds less than OWC's 6G - good way to save money for those wanting the performance but also looking for deals. :cool:
 
I know doing things like video or photo editing can involve a lot of disk I/O. Video files, naturally, are very large and manipulating them is no trivial task. That's why all the videographers are falling over themselves over thunderbolt.

With photo editing the demand is not quite as high, but still, complex photoshop documents with many layers can easily extend into the 1-2GB range, and if you have a high resolution stitched mosaic of multiple images, well it can easily reach several gigs per file. Of course you want to have a crapload of RAM as well but reading the files themselves from the disk can take up a lot of time too.

I don't know if SSDs are used a lot in server applications (price/performance seems too high, but enhanced reliability should be a bonus) but it's another area in which heavy disk I/O is expected.

Ruahrc
 
Just installed Mercury Extreme Pro 3G a few minutes ago and happy to report that Negotiated Link Speed is now 3 GBps and AJA System Test is showing write speeds of about 215 MB/s and read speeds at about 265 MB/s. Loving the new found speed.

Thanks again for everyone's input/advice/assistance.

I am getting 100Mb/s write and 265Mb/s read through AJA System Test on my MM 2009 2.66GHz with Intel SSDG2.
I see 3GBps under Negotiated Link Speed so is this Intel G2 such a slow poke versus Mercury Ext. Pro 3G in writing speed?
 
An interesting anecdote, I was moving a lot of data between the two 750GB 7200rpm HDs in my mini server today, and I was getting pretty sustained transfer rates in the 100MB/s range. Not bad!

Ruahrc
 
Hi,
I'm getting this on my 2009 Mini:
 

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I know doing things like video or photo editing can involve a lot of disk I/O. Video files, naturally, are very large and manipulating them is no trivial task. That's why all the videographers are falling over themselves over thunderbolt.

With photo editing the demand is not quite as high, but still, complex photoshop documents with many layers can easily extend into the 1-2GB range, and if you have a high resolution stitched mosaic of multiple images, well it can easily reach several gigs per file. Of course you want to have a crapload of RAM as well but reading the files themselves from the disk can take up a lot of time too.
I do all of the above as it's my business, but I've don't think any of the CPU-intensive video-editing applications out there can even process data at 6 Gb a second - that's more what I was getting at.

I'm looking forward to Thunderbolt myself since we frequently have to transfer HUGE files between machines & backup RAID arrays, but you'll only be able to realize those speeds in straight-up file transfers.

My work buddy has the OWC 6G SSD drive in his mini, I just have a Samsung 256Gb Sata-II SSD. We both get the same read/write rates, but he paid nearly twice as much for his drive as I did mine (his being only a 240 as well). :shrug:

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An interesting anecdote, I was moving a lot of data between the two 750GB 7200rpm HDs in my mini server today, and I was getting pretty sustained transfer rates in the 100MB/s range. Not bad!

Ruahrc
Pretty darn solid for non-SSDs! :)
 
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