Western Digital Caviar for iMac (Late 2006)

My iMac (late 2006) came with a Hitachi 500GB SATA-II hard disk, which I paid extra to upgrade from 320GB. Its SATA controller can only run at speed 1.5Gbps (SATA-I), kind of wasting the hard disk's performance. Anyway, it has been running slow and getting full (with less than 10% space left... even it's still some 30-40GB of free space). So, I wish to upgrade it to 1000GB or so, as the price dropped so much all these years. A 1TB drive is only $400 (USD50), a 2TB is $640 (USD80).

So far, I'm not consider Hitachi because it is hot. I don't have good impression with Seagate even the one in my office is Seagate. So, I go for Western Digital. My friend told me about their Caviar series and said "Go for Blue, not for Green".

The max capacity of Western Digital Caviar Blue is 1TB. It is only a double of my current drive. I'm thinking to get more than just a double. But... following is their product chart (3.5", minimum 1TB, SATA interface)

WD Caviar Black
Model #	Interface	RPM	Capacity	Cache	price
WD2002FAEX	SATA 6 Gb/s	7200	2 TB	64 MB
WD1502FAEX	SATA 6 Gb/s	7200	1.5 TB	64 MB
WD1002FAEX	SATA 6 Gb/s	7200	1 TB	64 MB	$603
WD2001FASS	SATA 3 Gb/s	7200	2 TB	64 MB	$1260
WD1001FALS	SATA 3 Gb/s	7200	1 TB	32 MB	$652
WD Caviar Blue
Model #	Interface	RPM	Capacity	Cache	price
WD10EALX	SATA 6 Gb/s	7200	1 TB	32 MB
WD10EALS	SATA 3 Gb/s	7200	1 TB	32 MB	$415
WD Caviar Green
Model #	Interface	RPM	Capacity	Cache	price
WD30EZRSDTL	SATA 3 Gb/s	IntelliPower	3 TB	64 MB	$1890
WD25EZRSDTL	SATA 3 Gb/s	IntelliPower	2.5 TB	64 MB
WD20EARS	SATA 3 Gb/s	IntelliPower	2 TB	64 MB	$662
WD15EARS	SATA 3 Gb/s	IntelliPower	1.5 TB	64 MB
WD10EARS	SATA 3 Gb/s	IntelliPower	1 TB	64 MB
WD20EADS	SATA 3 Gb/s	IntelliPower	2 TB	32 MB
WD15EADS	SATA 3 Gb/s	IntelliPower	1.5 TB	32 MB	$735
WD10EADS	SATA 3 Gb/s	IntelliPower	1 TB	32 MB	$420

There are questions asking why choose the Caviar Green. Here is one of the reviews (in Chinese) : 給我一個選綠盤的理由?西數黑藍綠盤對決.

Looking at the review, Caviar Blue is great choice. However, they don't offer 2TB version (yet?). So, I may either go for Caviar Black or Caviar Green.

iMac (late 2006)
iMac5,1
Core2Duo 2.16GHz, 4MB L2 Cache
DDR2 667MHz 2GB + 1GB (non dual-channel)
SATA 1.5Gbps link

Considering my iMac is that old, there maybe no differences between Caviar Blue and Caviar Green. The bottleneck falls into the onboard SATA controller.

So, shall I go for Caviar Green because I can store more data on iMac, without connecting a lot external drive? Or, shall I get Caviar Blue so that the iMac run faster? I may also get another DDR2 2GB so that the computer runs dual channel, which should be 8-10% performance boost.