Negotiated Link Speed only 1.5Gbps for 256GB SSD on 15" mid-2009 MBP?

Hi all,

As suggested in this forum, the solution is to "shut down" and "start" instead to "restart"!

- after a "restart", the Negotiated Link Speed is 1.5 Gigabit

- after a "shut down" and "start", the Negotiated Link Speed is 3 Gigabit

> if you "restart" (e.g. after OS update), just "shut down" and "start" again your Mac to recover the Negotiated Link Speed at 3 Gigabit.

It works for me (Crucial M4 512Gb - TRIM activated - MBP 5,3 - 15" - 3.06 Ghz) since 2 months.

Regards.

Great, thanks Tobit! Works exactly as you decribed... 🙂

Same here. Shutdown and start did the trick on my mid 2009 MBP 13" with a Crucial C300 256GB SSD ...looks like this is bug in the firmware. Thanks Tobit! 🙂

this fix doesnt work for an Intel 520 SSD on MBP 5,5

Simply cant get to 3gig

I'm on macbook pro late 2008, had the same problem with the sata1 negotiated speed on stock 5400 rpm hdd, upgraded to a Samsung 830 series 128 GB, now running correctly at sata2 speed. It's running blazing fast for such a old computer. I recomment Samsung over any other on a macbook, Apple knows why they are using them. Also tested a Corsair force, but on a different system (Mac pro), also running well for over a year and 1/2 now. I recommend Samsung though, plus Trim enabler. From press of button to desktop = 29 seconds, only 4 beachball spins. I used to wait 2-3 minutes to boot.

Doesn't work for me. https://discussions.apple.com/thread/4046514

i used daisy disk to remove lion app and re downloaded osx lion from app store and reinstalled lion osx 10.7.4 for and it remapped the link speed to 3 gbps..that was my fix.

Hi Mariussavin,

I also have a macbookpro5,1, and considering the Samsung 830. I have an Apple-installed "Apple SSD TS256" now, and the i/o lockups and beachballs are driving me nuts.

Does your machine consistently achieve the SATA2 link speed? Are the intermittent beachballs and i/o lockups completely gone now?

Thank you,

Andrew

SATA 2 negotiation is constant. No more lockups. It is like i bought a totally different computer just by switching the SSD ( i remember comparing it with a MBP late 2011 that a friend of mine has - mine boots and launches faster; the irony is that his MBP was SATA3, but Apple gave him a SATA2 drive, they seem to want to downgrade the hardware). I recommend Samsung 830 series strongly.

I have the SanDisk Extreme 240SSD, with the same issue. In my case, after having 1.5gbps I would restart then it would go to a negotitated 3gbps. Weird. So your recommending to shutdown then start?

SoySauceWDF wrote:

The same thing is happening to me, except it won't change to 3.0 even if I reset the SMC. I'd really like a solution so I can use more than half of my ssd speed.

Your SSD speed is less than 1Gb/s, the bus speed is greater than that so there is no performance drop involved, you are getting the full speed that the drive is capable of.

Schwa72 wrote:

I just installed a new Crucial C300 256GB SSD in my mid-'09 MacBook Pro (2.66GHz Core 2 Duo w/ 4GB RAM). I didn't have any issues with the install but I did notice that the negotiated link speed shown in System Profiler for the drive (under Hardware - Serial ATA) is only 1.5Gbps when 3Gbps is possible and the SSD supports 6Gbps transfers.

Here's what's really weird -- if I reset the computer's SMC, the correct negotiated link speed of 3Gbps shows up after booting...until I reboot the computer at which point it drops back down to 1.5Gbps. What the heck is going on here? How do I get the SMC to "stick" so the drive doesn't slow down after a reboot?

The drive transfer rate is less than 1Gb/s, there is no difference in transfer rate from the drive regardless of whether you use Sata1 Sata2 or Sata3, they are all faster than the drive.

timothy37 wrote:

I also have the same issue after installing a Crucial M4 256GB SSD in my MacBookPro 5,3 (mid-2009 15" 3.06ghz core 2 duo). Negotiated link speed is 1.5 and I have all updates (OS 10.6.8). The SSD is still pretty quick but if this computer is capable of 3.0gbps I'm wondering if it can be quicker!

The SSD is capable of 0.1 to 0.6GB/s, the bus it is connected to is capable of 1.5 to 3.0GB/s. As the drive is much slower than the slowest speed the bus can manage there is no more to be had.

Check this link for some measurements of an SSD on a 3G connection, nothing faster than .5G.

So after trying the restart instead of shutdown, I have been able to get 3gbps, but not consistantly. What I would do is shutdown, start then restart to get 3gbps. It worked the first 3 times, then failed the fourth time. I just dont know what the trick is. After it failed the fourth time, i restarted again and back at 3gbps. The good thing for me, is once it is at 3gbps, it will remain that way even in sleep/hiberation. just when shutting down and starting, it goes back to 1.5.

similar problem but with original SATA hard drive

https://discussions.apple.com/thread/4213129?tstart=60