Like pretty much all of the new mechanical drives that have been launched recently, Western Digital's WD7500BPKT Scorpio Black 750GB uses a form of Advanced Sector Formatting (ASF) technology. This uses 4K per sector instead of the old legacy 512 bytes per sector. The increase in sector size allows the gaps between sectors to close.
It improves areal density, in turn allowing for greater capacity per platter. It also improves formatting performance and, probably more importantly, gives greater data security and integrity.
To get to its 750GB capacity the Western Digital Scorpio Black WD7500BPKT uses two 375GB platters (discs). Because of the ASF technology these have an areal density of 520Gb/in.sq, slightly below the 541Gb/in.sq of Toshiba's 750GB MK7559GSXP.
Why all the fuss about areal density?
Well, it's important because it affects the performance of a mechanical drive. The higher the density of a platter, the more data passes under the read head on each revolution of the disc. This increases the sequential throughput.
On the flip side, tightly packing in smaller bits makes each one harder to target when the head is moving across the platter trying to access the data. Hence slightly slower random access times.
To put the performance verses capacity argument in some kind of perspective, for the same price as the Western Digital Scorpio Black 750GB you can pick up an SSD with just 64GB capacity.
However if you want try to match the 750GB capacity in SSD disk format, you are looking at something like the 720GB version of OCZ's IBIS HSDL drive, for which you won't be getting change from around £1,650 or more.
Huge capacity plus a fast spin speed would make you expect a largish price tag, but that simply isn't the case anymore. The Western Digital Scorpio Black 750GB WD7500BPKT still comes in well under £100.
One other standout feature is that Western Digital back the drive with an, albeit limited, warranty of five years.
All in all a very desirable upgrade for an older gaming notebook or a mobile workstation, or even a fast drive for a compact PC.
It's hard to find anything wrong with the Western Digital Scorpio Black 750GB. It has pretty much all you need for a small format mechanical drive; performance, capacity and good price.
Fast-performing, well-priced small format drive which would make an interesting solution for a number of platforms, not necessarily all notebook-based.