Hello ! This is my first time on a Witcher forum, so I'm not sure if this is the best place to ask:

I am upgrading my PC with a new video card, GTX 560 (no Ti). My processor will remain the Intel Core2 Duo E6600 2.4GHz that I have now. Motherboard is Gigabyte, 266MHz, I have 4G RAM and Vista 64 bit.
The question is: how much and in which way will the processor drag down game performance, or how will it impact the recommended settings.
I suspect that it will be the processor and motherboard that are going to drag down performance. I wish to know in which way and how much :D

My monitor has analog input, 1280 x 1024 , and I am considering getting a new one wich has digital input, 1920 x 1080 resolution.

Thank you !

PS: The game works fine on medium settings with GTX 560 and my old processor :) (medium settings were recommended by the game), though after I get my new monitor I think I'll lower the settings to improve FPS. As it is, it's a bit confusing when the screen changes rapidly (such as in fights or exploring). It could also be that the new monitor with greatly improved response time, better resolution and digital input will make it better, but the higher resolution will likely drag down performance.

Since I had to use the exact same cpu a few weeks back with a GTX460, I think I can give you a pretty accurate assessment. With my 1920x1080 resulotion, I was able to play on low to medium details, if you tweak out the less important features like motion blur etc. you can have a solid medium performance (should be even better with the new patch).
If you use your lower resolution, you might get even better performance.

Using the good gpu with the dualcore cpu and also my quadcore with a weak gpu, I can say, that TW2 really makes good use of every piece of hardware at it's disposal.

But... your cpu really just fulfills minumum requirement. A little quadcore would give you a lot better performance. Come to think of it, you'd need a new mainboard and RAM as well, I guess that is the biggest concern, as that is in effect a whole new pc. Well, you CAN run the game with the dualcore. Up to you, then.

I think you are going to see a processor bottleneck. The E6600 is barely above the minimum for the game, and this game uses a lot of CPU to manage the actors. Maybe you can find a used Q6600; they are very common. And most Gigabyte motherboards are suitable for overclocking; you can get 3 GHz out of a Q6600 without even trying.

Your RAM isn't a problem: the thing about RAM is to have enough of it, and how fast it is is secondary.

I might need to clarify on that, Witcher 2 can use more than 2GB of ram..that is why on certain systems you need to enable /3GB switch on 32-bit OS(like on my Win7 32-bit)..so that the game doesn't crashing after hitting 2GB physical RAM utilization at certain locations.

Just to be sure that my Kernel also has more RAM after 3GB (because 3.25 is limit on 32-bit OS with my AMD 6950 card), I enabled PAE and am using a modified version of Kernel to increase Physical RAM limit to full 4GB. Using another Kernel, via an option in bootloader (also with native Win7 32-bit kernel just incase I need to do win7 autoupdates).

Both are LGA 775 and the same generation (Conroe/Kentsfield, 266 MHz FSB). A Q6600 is just two E6600 chips in a single case. It would be rare for a Gigabyte motherboard to support one and not the other. The only important exception is motherboards with the Intel 945 Northbridge; none of these support quads. But you are right, it is always wise to check the manufacturer's CPU compatibility list.

Hmm... might explain my frequent crashes after a certain point in the game. Though I haven't seen it use that much RAM, it might spike. Would that explain the ctd's on save, though? I'll try it with the 3GB switch and see if my Windows will blow up in my face. ;)

Thank you for your replies, that was certainly informative and interesting !

The mothherboard might support quad core, certainly not more. I don't really want to upgrade that just yet, but if I might get a stronger processor for low cost (<90 euro base cost), I think I will. Perhaps a dual core i3-2105 3.1GHz ?

Still, Intel quad cores aren't exactly cheap, and a new dual core won't be very efffective with Witcher 2 (I read that there is a strong decrease in performance for dual cores, beyond apparent benchmark performance).

The good part about a minor upgrade with the processor is that it will delay the need for a major CPU + Motheboard change, and let me play Witcher 2 in better fashion :D

PS:
After checking, I found that i3 (which is dual core and more cost-effective) is not compatible, while older quads are (for example Core2 family).
So, I suppose cjrgreen was right about Q6600. I am going to get a quad that fits my motherboard. Even if they are not very high on a performance /price scale it will probably prove to be the best solution in my case.

The game works fine on medium settings with GTX 560 and my old processor :) (medium settings were recommended by the game), though after I get my new monitor I think I'll lower the settings to improve FPS. As it is, it's a bit confusing when the screen changes rapidly (such as in fights or exploring).

It could also be that the new monitor with greatly improved response time, better resolution and digital input will make it better, but the higher resolution will likely drag down performance.