I have a P4 3.4ghz CPU and the new ones (Dual Cores) have a far lower clock speed. It means nothing they say, but still: What Dual Core version would I need to surpass the speed of my current CPU? Does the lowest Dual Core do that? It is very cheap, which confuses me.

Edit:
nevermind

just look here for a nice reference.

http://www23.tomshardware.com/cpu.html

Thanks Simon!

I actually found a pretty nice chart over at Toms Hardware.

Edit: Haha :) Same url. Removed mine, couldnt hyperlink it anyway.

I am afraid that the answer is not as straight forward as all that.
Ok, basically there are two cases for applications running on a dual (or quad) core machine:
1) Single-threaded app:
The program is not multi-threaded, and so can only run on a single core anyway, which negates much of the speed gain. However, it is quite possible that it be given much more clock time on that one core (sometimes the entire core), than would be possible in a single-CPU machine, because the OS and other apps can use the other core(s).
2) Multi-threaded app:
Here the program has been multi-threaded, and provided this was done properly (not an easy task), you will see a good jump in performance over a singe CPU.
From personal experience, a 2Ghz Core Duo feels considerably more responsive than a 3Ghz P4, but it is entirely possible that some operations may be just as slow, or maybe even slower. In applications that are well written for multiple cores though, there is a definite speed-up, for instance in my case GCC often compiles large projects 3-5 times as fast on the Core Duo than on the P4.

The Pentium 4 has insanely high latencies. Thus, unless your code is stream processing, the MHz doesn't help. A simple add instruction may have three cycles of latency. On the Core architecture, they went back to cut down on latencies, so a 2.0 GHz Core 2 can often outperform a 3.4 GHz Pentium 4 even on a single-threaded app.

And, ironically, for the deeply pipelined compute tasks that the Pentium 4 can do well, you end up being memory bandwidth limited anyway, and the 1066 FSB Core 2 (or even 1333 Xeons) will out-perform the 800 FSB Pentium 4 systems.

I <3 the crap out of my Core2 duo.

Prices are dropping so if you like spending cash get the quad-core version. if you're a hardcore gamer HL2-Ep2 will blaze on that chip; plus it opens the gates for playing around with "massively" threaded game engine architectures.

If you're upgrading your PC I'll say that the biggest difference I've noticed in machine speed was upgrading from a single generic HD to a RAID0 array of the 10,000 RPM raptor disks. A lot of the noticible slowdowns in games is from reading stuff to or from disk. It also subjectively halves the boot time of XP.

-me

Thanks guys :) I am upgrading my system as a whole and was afraid these new cheaper chips would give me less performance.

I have decided to go with the E6600.

Quote: Original post by SymLinked
Thanks guys :) I am upgrading my system as a whole and was afraid these new cheaper chips would give me less performance.

I have decided to go with the E6600.

I made the same decision, because it's the first model to have 4MB cache.

Quad cores are just too expensive at the moment.

Quote: Original post by Lode

Quote: Original post by SymLinked
Thanks guys :) I am upgrading my system as a whole and was afraid these new cheaper chips would give me less performance.

I have decided to go with the E6600.

I made the same decision, because it's the first model to have 4MB cache.

Quad cores are just too expensive at the moment.

Yup it's the same cpu I ended up choosing since it's performance is almost the same as the next higher Intel cpu that cost 2x as much and also beats even the fastest AMD cpu in 99% of test. They even test on Vista x64bit to see if there is much a performance gain if any.
See here they even tested all newest quadcore Intel/AMD quadfx cpu to here.
"Athlon 64 X2 6000+, which draws more power at peak than the Core 2 Extreme QX6700 yet is often outperformed by the less expensive Core 2 Duo E6600. The Athlon 64 looks more competitive in its lower-end incarnations like the X2 5000+ and 4400+, which match up better on both performance and power characteristics against the Core 2 Duo E6300 and E6400."
"Many of our tests have shown the benefits of quad-core processors, but honestly, finding applications that will make good use of four cores is not easy—and the list of games that really use four cores is approximately zero. I'd probably grab a Core 2 Duo E6400 and overclock it until it started to glow, if I were putting together a system right now. I must admit, though, that I have an almost irrational fondness for the Core 2 Quad Q6600, probably because it's the most energy efficient processor in our Cinebench power test. The thing is by no means a great deal—two E6600s will set you back over $200 less than a single Q6600"

Quote: Original post by hplus0603
The Pentium 4 has insanely high latencies. Thus, unless your code is stream processing, the MHz doesn't help. A simple add instruction may have three cycles of latency. On the Core architecture, they went back to cut down on latencies, so a 2.0 GHz Core 2 can often outperform a 3.4 GHz Pentium 4 even on a single-threaded app.

And, ironically, for the deeply pipelined compute tasks that the Pentium 4 can do well, you end up being memory bandwidth limited anyway, and the 1066 FSB Core 2 (or even 1333 Xeons) will out-perform the 800 FSB Pentium 4 systems.

Yup, the FSB makes a big difference. I had on my old computer a P4 1.6Ghz. My laptop has the Core2Duo, also 1.6Ghz. Running a task that I know uses one thread only, I still close to double speed at times, and others, more than double. I'm glad I waited and didn't mess with P4s at 3.2Ghz with "hyper-threading" crap on them. Most games I have seen run with one thread, but a lot of development tools can use well the dual core CPU.