I think that comparing CPU clock speeds within a family is ok but there are too many factors and the situation is too complicated to compare across families or vendors.
People got too concerned with absolute clock speed and the arms race has died down a bit given that it got to the point where in some situations a slower clock CPU ran stuff quicker.
You should always be thinking about overall system performance and the CPU is just one of many factors in the chain. The biggest bottleneck in PC's is generally the RAM path. Random accesses to RAM is very expensive which is why there are multiple layers of cache to them. Even then the situation is not clear as faster RAM chips on the same bus does not appear to make more than a few percent difference.
From the games point of view, nearly the whole story is about the video card because when it has a lot of video ram and lots of pixel shader power, the CPU is not so involved as it used to be. The geometry for the game is held on the card and the textures and shaders are also on the card and the GPU does the actual drawing of it all. The CPU has been relegated to the scoring, the UI, the game physics and the AI.
So, hot CPU + duff video card means slow game. Hot CPU and video card but slow path to RAM is also bad. And you also don't want to burn the CPU cycles doing sound processing so get a sound card which has a capable sound processor.
Basically a fast system is where all of the hardware units are firing on all cylinders. And a cost effective fast PC is where all of the hardware units are balanced in speed so that no one bit of the system is significantly slower than all of the rest.
The CPU does need to be good but its not the whole story and the raw GHz of it is not the best indicator any more.
Most games are multi-threaded and even if they are not then the OS and other processes on the system will want a time slice so a dual core is almost always better than a single core. Often one core is fairly idle but when playing games it ought to be in full use. A good game developer would try to balance the workload amongst the hardware units available so you try to balance the CPU work with the GPU work and the CPU work should be made available in chunks that can be given to each core concurrently.
People got too concerned with absolute clock speed and the arms race has died down a bit given that it got to the point where in some situations a slower clock CPU ran stuff quicker.
You should always be thinking about overall system performance and the CPU is just one of many factors in the chain. The biggest bottleneck in PC's is generally the RAM path. Random accesses to RAM is very expensive which is why there are multiple layers of cache to them. Even then the situation is not clear as faster RAM chips on the same bus does not appear to make more than a few percent difference.
From the games point of view, nearly the whole story is about the video card because when it has a lot of video ram and lots of pixel shader power, the CPU is not so involved as it used to be. The geometry for the game is held on the card and the textures and shaders are also on the card and the GPU does the actual drawing of it all. The CPU has been relegated to the scoring, the UI, the game physics and the AI.
So, hot CPU + duff video card means slow game. Hot CPU and video card but slow path to RAM is also bad. And you also don't want to burn the CPU cycles doing sound processing so get a sound card which has a capable sound processor.
Basically a fast system is where all of the hardware units are firing on all cylinders. And a cost effective fast PC is where all of the hardware units are balanced in speed so that no one bit of the system is significantly slower than all of the rest.
The CPU does need to be good but its not the whole story and the raw GHz of it is not the best indicator any more.
Most games are multi-threaded and even if they are not then the OS and other processes on the system will want a time slice so a dual core is almost always better than a single core. Often one core is fairly idle but when playing games it ought to be in full use. A good game developer would try to balance the workload amongst the hardware units available so you try to balance the CPU work with the GPU work and the CPU work should be made available in chunks that can be given to each core concurrently.
[[Wishes he could help more....]]
