_j5689_ wrote:
I don't use AMD so I don't know how it would work for an Intel.
On Intel chips you can't alter the multiplier at all, but increasing the FSB works for Intel chips just like it does for AMD chips.
Let me give you a little overclocking lesson.
1. When AMD and Intel make CPUs they do not make them to be certain speeds. All of the chips are manufactured exactly the same. Once the chips are made they are speed tested to determine how fast they can run at the chip's rated VCore settings. This is called binning. The thing is that AMD and Intel are good at tweaking their manufacturing process. As a result, a very large portion of the chips they make actually bin out at the upper end of their speed grades. In order to meet demand they will take chips rated at higher speeds and bin them down to run at lower speeds. This is what overclockers attempt to use to their advantage.
2. Some people may wonder why it is necessary to change the VCore (CPU voltage) when overclocking. The reason isn't that the chip needs more power. The reason this is done is because CPUs are a binary device. Just as code is either 0 or 1, a CPU registers these as on or off states. An off state is V0, where an on state is VCore; the voltage at which the CPU is rated to run. As you increase the speed of the processor it has less time to determine whether it needs to be in V0 or VCore state. When it fails to do this accurately you get errors. Increasing the voltage increases the VCore state, thus widening the delta the CPU has to properly determine a V0 or VCore state. Obviously this will only get you so far. The quality of the silicon, or any flaws in the chip will also determine how far you can go before increasing the voltage no longer provides any benefit.
3. Memory dividers. Optimally you would want to have the RAM bus and FSB at the same speed. This reduces any latencies associated with translation that needs to occur between two busses running at different speeds. However, it is usually the case that the FSB will go higher than the RAM can accommodate, so a divider is used. As an example, the RAM in my computer is not capable of running at 256MHz. As a result I must use a RAM divider. The divider works like this. Where the default bus speed for the CPU is 200MHz I set the RAM to run at 166MHz. As I increase the FSB to where it is now, at 256MHz, the RAM remains in a more manageable ~208MHz. Yes, there are some penalties for this, but the increase in CPU speed outweighs them.
You should also realize that many people are enthusiests. They will spend extra money on motherboards and high-end RAM to overclock, with the resulting bill being larger than if they had simply bought faster parts. It's kinda like the guy that spends megabucks suping up his car even though he doesn't race it, and the top speed limit is 75MPH. It's a hobby, and we enjoy doing it. Up until a short time ago I used water cooling. Did I need to? No, but I did it because I could.
