CPU upgrade no performance change

Hello,
I am just going to throw this out here.

I upgraded my CPU over the weekend going from a AMD 64 3200+ to a x2 6000+. So I have upgraded my clock speed by +50% (+1 gHz) and added a second core. I was naturally expecting to see quite a significant difference. Not for normal stuff because my old cpu could handle most of the day to day stuff quite happily but it struggled with some gaming applications. What I expected to see was an increase in my frame rate with some of the heavier games.

Looking at the benchmark charts I was expecting to see a difference somewhere in the x2-x3 magnitude. I know that this is not necessarily the case because it depends if the software has been written to take advantage of multicore processors but solely upgrading the clock speed by 50% and a lot of the core processes (antivirus normal housekeeping background stuff) probably being taken care of on one core while gaming on the other I expected a noticeable significant difference.

Imagine my disappointment after spending a week like a kid waiting for Christmas for my CPU to come to discover that after putting the cpu in there was no noticeable difference in performance.

I bought the new cpu 2nd hand but it seems fine my system is giving me the correct info i.e it identifies the cpu and quotes 3.01 ghz as the processor speed. Task manager shows 2 cores when I click the performance tab but I am tempted to put the old cpu back in and resell the new one for all the performance increase it has given me!

This has turned in to quite a lengthy post but I am a 7 year old kid again after waiting excitedly for my new mega drive I seem to have got a new master system but in a different colour (this is for illustration purposes I am not a console boy, Commodre 64, Atari ST, Amiga 1200, pc shows my age).

To get back to the point is this right or is there something wrong somewhere. To give an example
GTA IV
3200+ 6.1 fps
6000+ 6.2 fps

okay that was a bit cathartic and cheaper than a couch. any comments thoughts?
cheers.

nvidia geforce 7500 gt (super) with a gb of dedicated ram but after I downloaded the latest driver from nvidia about a month ago it is no being recognised as a 8500 gt for some reason

Your GPU is way, way underpowered for gaming.
Upgrade to a proper GPU then compare the old CPU to the new one...

Does your motherboard support PCIe or are you stuck with an old AGP slot?

Download GPUz and use it to check which GPU you have, it probably is a 8500GT as the 7500LE has a max of 256Mb of RAM.
Regardless, both of these cards are very weak and the GTA port is a poorly coded resource hog.
I would not be surprised that, even with the old CPU, your system is GPU bound in this game.

Also, have you checked for a performance increase in any other games or applications?
Undoubtedly, your new CPU is much more powerful and you should see great performance increases in any non GPU intensive tasks.

With a minimal budget, consider saving for a 4670 512Mb GPU for around $50 after MIR.
It will quadruple the performance of your current 8500GT and only draws a few more watts so you should not have to worry about upgrading your PSU.
Be sure not to waste your cash on the 1Gb version, the extra RAM will give you no performance increase.

Computer games use graphics cards to do the dirty work; the CPU does all the leftover things (sound, AI, network, rasterizing) the GPU does the hard work. So if you would put 'weights' on how important both are to gaming, i would say its 30% to 70% (CPU vs GPU). So spend your money on GPU when you're a gamer, since its the primary performance factor in gaming.