I'm currently using a 1 TB caviar black as my main drive and a 1TB cavair green to store my music and movie's.
I use my black for everything: games, documents, photo's and begun to notice that my black is starting to run a little slower (400GB full). The green experience's a 3-4 second lag when wake it from its idle stage, but otherwise equally responsive.
Currently, I am thinking of buying another internal HD. I may run both blacks in Raid 0 or get the 2TB as the boot.
The WDC Black has two processors for handling I/O operations. The cache is there to serve as a buffer while the two processors decide in what order the I/O instructions given to it should be executed to optimize performance. Larger cache is better.
Typically, newer generation, same edition hard drives (e.g. An new WDC black vs. older WDC Black) is better. Note however, that WD's more recent drives turned off the ability to change TLER or time-limited error recovery. This removed feature can cause RAID arrays to fail constantly because of drive "not responding" due to it's error correction algorithms. Only WD's enterprise RE drives are advertised to run in a RAID array.
That said, you might consider getting a Samsung Spinpoint F3 1TB. They've been gaining ground on WD and Seagate lately. Plus, they can be used easily in a RAID array.
I wouldn't suggest using the WDC Green as a boot drive, although I'm using a 1TB variant as my boot drive now. I don't have the budget for a dedicated fast boot drive, so I don't have much of a choice. It's slower compared to the 1TB (or even 500GB) WDC Black, and will surely lose to the Spinpoint F3. Greens are excellent as data storage however, because of their low power consumption and ample average throughput.
Well, you will only really gain performance if you have a lot of simultaneous I/O requests. The cache, as I've said before, acts as a buffer. But if for example, you are just copying a file from the hard drive, then it is just one I/O request for a linear read. Since the physical spinning hard disk is slower than the cache, there is no performance gain. If however you are copying files while defragmenting, and listening to music and browsing the web all at the same time with the hard disk as your sole source of data, things will probably be different. The HDD's processor can change the order that the I/O requests are performed, in such a way as to optimize the work of the HDD and minimize latency.
This is all from the top of my head. I'm sure there could be more benefits of a larger cache, but in short: more cache gives the HDD more room to decide how to optimize I/O, which gives you the best performance.
SSDs will drop prices eventually. I might consider getting one once the good ones hit 100-150$.
get the spinpoint and format only 25% of the full cap. Don't really need the full 1 TB capacity for a OS drive. When you format only the 25% or less, the drive only travel to the fast region on the platter. This will decrease access time. Move the programs to the 1tb black, you can do the same 25% format scheme. Keep the green at full cap for you personal data. Also move paging files and temp to the green. Those can improve your loading time with windows and programs. HD is the bottleneck so spread out the task among many drives.
Sorry to resurrect an old thread but I hadn't heard or read this before. I have heard that performance is reduced once you occupy >50% of a drive's capacity so reducing the partition to less then that seems a smart thing to do unless you need the space.
Has anyone run a bench mark with this methodology?