Advice on HDD upgrade for gaming setup

[amsga]

I am currently using 2 Western Digital Caviar Black Hard Drives.
A WD1001FALS 1TB as my current Operatring System drive, without any partitions and a WD2002FAEX as my data and games drive.

I am planning to go for a Samsung 840 Evo 512 GB version in the future for purely my Operating System and another 4TB hard drive for my data and games.

I was wondering if there is a noticeable performance hit if I were to choose the WD Green (WD40EZRX) over the WD Black (WD4003FZEX) version?

 

[Emerald]

you will most likely see a performance hit due to the firmware settings of the Green drive.

The drive will spin down after a short amount of inactivity; therefore, it will have to spin up again before accessing data.

 

[SuperSoph_WD]

Hey there, amsga!

Yes, your performance will decrease if you choose the WD Green drives over the WD Blacks, especially in a gaming rig.
WD Greens as Emerald already mentioned will spin down after some time of inactivity.
This will hit your gaming experience and slow down your PC performance in general.
WD Greens are designed for secondary storage, they run cooler but not as fast as WD Blacks. They are reliable as a backup storage as well, but not really recommended to use for gaming.
http://www.wdc.com/en/products/products.aspx?id=780
WD Blacks on the other hand are specifically for gaming and demanding applications, they offer high write/read speed and performance with 7200 RPM and 64 MB cache.
http://www.wdc.com/en/products/products.aspx?id=760

Hope this helped.
SuperSoph_WD