I installed a brand new Seagate ST3500320AS hard drive into my Apple iMac Aluminum (24", 2.4GHz, 4GB RAM) in place of the stock Western Digital 320GB Caviar (8MB cache) to obtain faster performance. Once installed, I formatted the new drive in Mac OS Extended (Journaled) and installed a fresh copy of Leopard.
Not very long after the instal, I began to notice that Leopard began to perform slower and would hang-up much more than before. I would notice a pause before opening a program and running Time Machine made it impossible to perform any other tasks simultaneously. The new hard drive was causing Leopard to perform much slower than the WD Caviar drive.
I read posts and found that people were experiencing issues with the cache not being fully utilized. Seeing as Leopard doesn't use drivers, I still looked into that possibility. When I open system profiler, one of the Specifications in Serial-ATA devices is "Queue Depth" which reads 32, which I assume is the cache for the drive (please correct me if I am incorrect). The ST3500320AS hard drive is also revision SD15, which I believe is the newest (again, please let me know if that is wrong).
Getting more frustrated, I decided to purchase Drive Genius by Prosoft Engineering. This software allowed me to benchmark, defragment and deep scan my hard drive (via a bootable DVD with the primary hard drive unmounted) to check for faults. After running the deep scan, no bad blocks were detected. Upon running the benchmark, I was obtaining sustained reads/writes of up to 110MB/sec. which is up to par with Seagate's specifications for the drive.
I also removed the jumper of on the drive so that I could utilize the SATA II speeds. The old Western Digital Caviar that I removed also uses SATA II. The model number for the removed drive was WD3200AAJS.
Could somebody please just tell me that I am not taking crazy pills? Is there some hidden setting or something I don't know about? Although it's nice to have the larger drive, I wanted faster performance and got just the opposite. Any input is welcome, I really need to figure this thing out before I pull out the rest of my hair. All the specs are listed below.
ST3500320AS (SD15 Revision) -7200.11 -500GB (32MB cache) -SATA II (3.0GB/sec.)
iMac 24" Aluminum (Purchased Jan. 2008) -2.4GHz Intel Core 2 Duo -4GB DDR2 SDRAM 667Mhz -Mac OS X 10.5.2 (Leopard) -Boot ROM version: IM71.007A.B03