Mathias, Do you have an Early-2011 Macbook Pro 15"?

I have the 13", primo 2011, so i believe it is the same controller.

I found the issue.  I had a corrupted Time Machine USB disk and when the backups would start it would lock everything up.  As soon as I removed the bad USB drive everything went back to normal.   Hasn't locked up since!

I have 15" early 2011 as well. Actually, I have tried to put a drive into another laptop of the same model with a clean OS install -- same problems, so it's clearly reproducible.

After dicking around with the TRIM tools I came into conclusion they have nothing to do with the hangs. With MBP  5,1 running 10.6. there seems to be no sensible way to avoid the 20s beach ball once every 5 minutes.

The spookiest bit I found was someone doing hacked EFI images that "should fix" the issue but gladly there wasn't one available for 5,1 so I skipped that. Back to spindles it seems

I have an Early-2011 that has 6 Gbps link speed and have no problems.  I heard that the first few months the controllers were only set to 3 Gbps.  Figure out which one you have by going into About This Mac and then selecting System Report...   Select Serial-ATA and you'll find teh Link Speed and Negotiated Link Speed.  I'm curious which one you've got.

To confirm, my Early-2011 is doing fine with the Intel 520 480GB SSD.  My issue was a corrupted USB Time Machine backup drive.

I always had 6 Gbps. I have the issue without using Time Machine at all.

Maybe I should add that the problem has actually improved quite a lot. Only rare freezes now. I did many things, but I suspect clearing caches was what actually helped (emptying ~/Library/Caches and then reboot, you can try and see if it helps you).

I've tried and that didn't help unfortunately. Besides, I've got the same problem on the clean Mac OS install.

Does anybody know what's the current version of the firmware of 520, hopefully Intel will be issuing the fix? I've read the 320 about Intel and Apple support pointing fingers into each other, which is really sad. From my perspective as a customer I would expect Intel to fix the issue, since Mac worked perfectly before with x25-M and the problems were introduced when I upgraded to 520. It would be really great to get at least some comments on the subject from Intel.

Mine shows 400i. See below:

INTEL SSDSC2CW480A3:

  Capacity: 480.1 GB (480,103,981,056 bytes)

  Model: INTEL SSDSC2CW480A3

  Revision: 400i   

  Serial Number: masked 

  Native Command Queuing: Yes

  Queue Depth: 32

  Removable Media: No

  Detachable Drive: No

  BSD Name: disk0

  Medium Type: Solid State

  TRIM Support: No

  Partition Map Type: GPT (GUID Partition Table)

  S.M.A.R.T. status: Verified

  Volumes:

disk0s1:

  Capacity: 209.7 MB (209,715,200 bytes)

  BSD Name: disk0s1

  Content: EFI

New HD:

  Capacity: 479.24 GB (479,244,222,464 bytes)

  Available: 131.94 GB (131,940,610,048 bytes)

  Writable: Yes

  File System: Journaled HFS+

  BSD Name: disk0s2

  Mount Point: /

  Content: Apple_HFS

  Volume UUID: masked

Recovery HD:

  Capacity: 650 MB (650,002,432 bytes)

  BSD Name: disk0s3

  Content: Apple_Boot

  Volume UUID: masked

These freezes are not Mac specific. I encounter the same thing in Windows 7 on a Lenovo W520 ThinkPad. The hard drive light comes on and stays on. The system is completely unresponsive and I have to hard reboot.

There is really no one who fixed this issue? What did you do guys with your non-working SSDs?

I experience all the symptoms described in this thread. I enabled TRIM, disabled Time Machine, no success. Still 30s freezes repeating on a random basis. Sometimes once an hour, sometimes every five minutes. My patience is over and I have replaced it back to the original drive.

A friend of mine put the SSD into his thinkpad and run Linux on it. No issues at all. So it seems the problem is in Macs. Either OS X or hardware.

have the same freezes on my macbook pro late 08. using a 120gb 330 ssd with mountain lion (clean install)

Same issue — MacPro'11, 120 gb Intel 520 SSD. TRIM or hard drive sleep settings don't help; latest firmware version installed. Especially often the freezes happen when both SATA3 SSD and SATA2 HDD are accessed at the same time (eg. copying). Considering some posts attributing the issue to crappy sata2/3 compatibility in the controller, I tried one solution and it actually seems to work!

Originally I had the SSD in the optical bay. I have simply moved it to the HDD slot and the hard disk into the optical bay. I have still my fingers crossed, but it is 30 mins into the boot and there seems to be no hangs or freezes so far!

I think, the issue indeed is related to sata controller. Probably the ports used by the optical drive have a different controller than general HDD array, probably its sata2. So when a sata3 device is connected - the controllers just go mad.

Did anybody else manage to solve the issue this way? What about sata3 hard drives, does anyone have an experience in running these through 'optical bay' ports?

I had the SSD placed instead of the old drive and the old drive put into the optical bay. This setup does not work either. The SATA negotiated link speed for the SSD was 6gbps.

Well, yes, it does not eliminate the problem completely, but I am now getting hangs about once per day, while the previous setup would freeze every several minutes, rendering the machine unusable.