Thanks all for the advice and comments. Yep, OS is on SSD. The one problem I had was working out how to access the HDD. I eventually found the hardware management file in control panel, and remembered I had to allocate a drive letter there & quick format, plus making it active. What a relief that was. It was driving me nuts until I had my blonde eureka moment lol.
This has been my dream machine for 2yrs now and this past Xmas I finally had the money to get the parts and build it. I ummed & arred about the Revo drive for a while due to the cost ($739 at UMart, Milton, Brisbane - the cheapest!). In the end I just couldn't resist getting it given the reviews. I did a bit of downgrading on my wish list getting a 850 PSU instead of the Corsair 1200PSU, and decided to only get one PCI-E graphics card instead of two, 24" monitor instead of 27" to save on overall spending.
I had hoped to get the Gigabyte G1 Sniper 2 motherboard, but they were sold out everywhere. Took me a bit of fiddling to work out the whole SSD & HDD combo; and had to remove the heatsink & CPU, then refit it (thank-you Atomic edition 131 troublshooting) as it wasn't recognising the ram at first. But all is good now!
I can now finally play Mass Effect 2 for the first time in prep for ME3! Whoohoo :D