So more ghz does not equal better performance ??

do what all people do.
Look up reviews.

Or better yet we find a database full of benches.
http://www.anandtech.com/bench/CPU/2

DC7600??

A cpu is judged by it's ghz, if your judging 2 cpu's from the same generation/series.

For instance a 3ghz Pentium 4 is faster than a 2.8ghz Pentium 4, but slower than a Core 2 duo at 1.86ghz.

Because C2D is a newer, faster clock for clock architecture.

A dual core anything is faster than a single core anything. However certain dual cores can still be faster than a certain quad core, depeding on the speed of the cores and the architecture.

I'd take a p4 3ghz over a c2d 1.86ghz for single threaded apps.

dc7600? You mean an intel dual core e7600?

A single core of the core2duo 1.86ghz is equivalent to a p4 3Ghz+ so I would take a c2d over a p4, even over a PentiumD !! The c2d also overclocks way higher that a p4 or pentiumD while consuming less power and being a lot cooler than any pentiums... My c2d e6300 defaults at 1.86ghz but is currently running at 3.06ghz on air cooling so p4 is obsolete here.

Then you would be a complete idiot.

Hi fuggles   . That is not the real truth.   If you do not like to overclock,then the more GHz you have the better on average it is.   If you over clock,then you can go a little down and overclock to your delight.   I still think though that you're better off with more GHz in case you do not want to endanger your cpu or your pc.  

Take notice of "Wish I Was Wealthy" and that should take care of you.   If you can't read or some thing like that then you'll need the special attention of someone that has got plenty of time,but do not listen to too many amd bulldozer fans and end up buying'em or you may end up runing out of diesel.  

Fuggles,

What are you wanting to do with your PC, and what kind of budget are you on? The Pentium 4 processor was a decent core (I have one myself), but it is outdated. Pentium 4 was based on Netburst architecture which is now 3 generations back from the current Intel architecture, Sandy Bridge (or 4 generations if you count Core and Core 2 as separate, I am not sure about this) You should do some reading on the evolution of Intel cores over the last 10-12 years so that you have a fair idea where all the different iterations and architecture changes fall. Pentium is still around (not Pentium 4), it is available in dual-core; now sort of on the low-midrange of offerings, where once it used to be King. Do you have an old motherboard that you don't want to replace that only supports cores from the Pentium 4 era? How tight is your budget? If you are looking at current processors I would guess that an i3 (the new top range from Intel is split into 3 subranges, i3, i5, and i7) dual core would outperform the newest Pentium (dual) core by a safe margin, and not cost a ton more, unless you are on a shoestring budget. As far as single vs. dual, I think that when they started making dual cores with the "Core duo", they always outperformed single-cores; one of the reasons they went multiple core is they were hitting some limitations with heat dissipation and other issues with the single cores, even though they clocked the latest versions back in 2005-2006 at up to 3.8 Ghz. Sorry for the rambling, hope this helps!

Overclocking has absolutely nothing to do with his question.

To use some simple terms:

GHz measures the number of CPU cycles per second. Think of each cycle as an oppertunity for the CPU to do some work. More cycles, in theory, means more work gets done.

Just as important is Instructions Per Cycle (IPC). IPC simply is a measure of how much work a CPU performs every CPU cycle. This can vary based on the type of work being done though, so its hard to measure. IPC is VERY dependent on the underlying CPU architecture.

For instance, if you had a 3.0 GHz CPU that could execute 1 Instruction Per Cycle, then a CPU that ran at 1.5GHz would have to average 2 Instructions Per Cycle to have the same performance.

So "speed" in GHz is only one measure of a CPU's performance; its IPC is another.

One of the fastest Intel® Pentium® D processors that we ever release was at 3.73GHz Extreme Edition. If you compared that processor vs. the Intel Core™ 2 Duo e6400 at 2.13GHz at that time this site had done a series of benchmarks where you could compare the 2 of them together. Out of the 20 benchmarks the Intel Core 2 Duo e6400 outperformed the Intel Pentium D 3.73GHz EE in 16/20 and only just beaten in the other 4. When you think that this was a $200 processor vs a $1000 processor it is easy to understand why the Intel Core 2 Duos were such a big improvement over the older processors.

Christian Wood
Intel Enthusiast Team