SSD causes freezes and beach balls I replaced my MacBook Pro optical drive with an Agility 3 SSD from OCZ, currently operating at SATA I speed only (it should run at SATA II speed, but that's another story). After a clean install of Mac OS X Mountain Lion, I noticed a few problems that made the whole user experience nearly unbearable: constant beach ball cursors and unexpected freezes and pauses (up to one minute) when editting basic system preferences, copying files, using Safari, etc. Agility 3 SSDs have their own Trim manager, so I applied no hacks whatsoever. Here's what I've done so far:


Made several clean installs of Mac OS X Lion on the SSD: all problems persisted;
Enabled Mac OS X native Trim support, using Trim Enabler: didn't notice any changes;
Didn't install any software and didn't use the HD: all problems persisted;
Ran a "Verify disk" scan using Disk Utility: no issues returned.


I assume the problem is related to the SSD, because these beach balls and pauses started happening right after I installed the SSD. I do notice my Mac Book Pro is much faster though, whenever these issues don't freeze it. These are my relevant specs:

MacBook Pro 5.1 (late 2008):


2.4 GHz Intel Core 2 Duo;
8 GB 1067 MHz DDR3;
SMC version: 1.33f8;
Sudden Motion Sensor: Enabled.


Agility 3 SSD:


Model: OCZ-AGILITY3;
Revision: 2.220000;
Serial Number: OCZ-F2YXP9LB8741651B;
Native Command Queuing: Yes;
Queue Depth: 32;
Medium Type: Solid State;
TRIM Support: No;
Partition Map Type:   GPT (GUID Partition Table);
S.M.A.R.T. status: Verified.


Here are some similar issues I found when browsing through Apple discussion forums, all with the very same Agility 3 SSDs:


Macbook late 2009 - SATA III SSD issues
SSD beach ball freezes
occasional stalling


I guess I should be more specific and run some sort of diagnostics, but I honestly don't know how to do it. Is there anything I should do to provide more information on this issue? Any suggestions would be much appreciated, as I totally depend on this MacBook Pro to work and procrastinate.

Quick update: I just checked my System Report and my SSD is running (only) at SATA I speed, while it should only have backwards compatibility with SATA II. Maybe that's the problem. I just don't understand why it's not running at SATA II speed, as is the other HD I have on my Mac Book Pro (which, by the way, only supports up to SATA II).
This may also be an issue with the ICH8-M AHCI SATA interface chip. I have a late 2008 MBP that came with a 250 GB HD. I upgraded to a 640 GB and had endless beach balls. Turns out the models with a ICH8-M AHCI and a PATA superdrive interface cannot be upgraded higher than a 320 GB 7200rpm HD. Anything faster or larger will stall out as the FW for the ICH8-M AHCI cannot be upgraded beyond SATA I speed without killing the PATA interface.
Some models with a ICH8-M AHCI and a SATA superdrive interface can be upgraded with a FW update released by Apple.
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