Enlighten me, geeks!
 

So it's almost time for a new PC...this one isn't terribly old (4 or 5 years) but upgrading it not really an option. So my question is how do dual/quad core processors stack up against old school single processors? Aside from the obvious advangtage of using two processors sandwiched together on a single circuit, how do they stack up as far as speed? I always see relatively low speed listings for dual processors...maybe something like 2.1GHz. But since there are 2 processors is that like 2.1GHz per processor or altogether?

Also, is it really worth getting a system that's factory overclocked? Yes, I know I could probably do it myself, but I prefer a computer that's not broken as would almost surely be the case if I did it myself.

ive got duel 1.6 ghz's in my laptop and it seems to run single programs a bit faster than my 2.5ghz, but alot faster when your doing 2 things at once. there very well could be other factors, so take it as is

as far as overclocking, ive always been one against it since i'd rather run my shit a little bit slower and have it run cooler thus safer.

also im sure you know, but get as much ram as possible.

Oh yeah...I'm almost not considering anything with less than 4GB. Curiously, the other day I say a custom system with 16GB of RAM. Seemed odd to me because I was under the impression Windows couldn't use more than 8GB.

no clue to tell ya the truth

Well...the more I think about it the 64 bit version of Windows can probably support more RAM. But I'm pretty sure the 32 bit system only supports 8GB.

sounds right. i know im limited by the space in my laptop for ram, but im pretty sure on a 64 bit you can get 16gb now that i think about it a little more. also, get vista and learn it. a few of my friends swear its terrible and use XP still when in all honesty i have 0 complaints with vista now that i understand how everything works and where it is. it took a bit but worth it now and i still find new cool shit daily that i didnt even know i could do. it may run some older 32 bit programs worse than xp but you dont wana get a new machine to run old programs your old box can.

That is correct.. You need a fully compatible 64-bit system to run that much memory.

Actually 32-bit supports 4GB and 64-bit Windows XP OS supports 128GB of physical RAM.

Here are some other memory support stats:
64-bit vs. 32-bit architecture
Address space 64-bit Windows 32-bit Windows

Virtual Memory: 64 Bit - 16TB / 32 bit - 4GB
Paging file: 64 bit - 512 TB / 32 bit - 16 TB
Paged pool: 64 bit - 128 GB / 32 bit - 470 MB
Non-paged pool: 64 bit - 128 GB / 32 bit - 256 MB
System cache: 64 bit - 1 TB / 32 bit - 1 GB

So obviously, if you run memory intensive apps you will see the greatest benefit with a 64 bit system.