The Hard Drive As A Bottleneck
Many workplace PCs are still equipped with the comparatively small drives they shipped with. 40 to 80 GB disks are quite common, but in a number of cases, users are beginning to feel constrained by these sizes. This is hard to imagine given what we were using for hard drives just a few years ago, but think about all of the files that the average user accumulates over time: digital videos - more and more often in the very large HDTV format - music files, pictures from digital cameras and more. All of this data requires storage space.
Yet the increase in capacity isn't the only point in favor of a new addition or upgrade. Another important factor should always be the potential speed increase that a new drive can offer during everyday work. After all, the hard drive companies keep refining their products with every generation.
While the first generation of 7,200 RPM drives offered comparatively low transfer rates of about 25 MB/s, current hard drives can sustain peak rates of just over 70 MB/s. Therefore, replacing a 40 GB drive with a current generation model would noticeably speed up everyday work on an average Windows PC - and this holds true for any current drive.
As the numbers above show, the hard drive is still the slowest component by far in any computer. The system memory juggles several gigabytes of data per second, while the processor cache has to cope with even larger amounts of data.
It's not hard to imagine scenarios in which the hard drive becomes the bottleneck: delays can occur during Windows start-up, when launching applications or when swapping system information to the page file or simply saving a large project. These operations can be sped up with a newer, faster drive.
Of course it goes without saying that the system still needs to be equipped with a sufficient amount of memory. Otherwise, Windows will have to resort to swapping system files to the disk, which, as mentioned above, can slow the system to a crawl. As a rule of thumb, 512 MB is considered sufficient for smooth work today, while 1 GB allows users to run several more demanding tasks simultaneously. Adding even more RAM only makes sense in special cases.