This question will probably result in a few snickers but I gotta ask. Why is the hard drive speed important when running games, The reason I ask is that I am not able to run my game unless the disk is in the CD/DVD drive. so is the gaming not running off of the CD drive and not the hard drive?? I am sure I am completely wrong so can some please explain why hard drive speed is so important?
Hard drive speed is for reading and writing to the drive. This means the game will install faster, load faster and you can save faster. But saved games are relatively small so you won't generally notice a difference between a fast and slow drive.
You must insert the DVD or CD in the drive because games are copy protected. It is to ensure that you have a legal copy of the game that you bought in a store.
The primary slowdown as far as the hard-drive is concerned is loading times. Half-Life 2 for example has to load content every time you move from one area to the next. The drive churns quite a bit during this time, but once the loading is complete it generally doesn't have much to do. The focus then shifts back to CPU/GPU/RAM.