32 to 64bit aint a big leap, why?

[metalmackey]

Hi guys,

I was just wondering why going from 32bit to 64bit CPUs doesnt seem that much better compared to going from 8bit to 16bit or 16bit to 32bit, where there was a big difference. Most 64bit CPUs are still running in 32bit mode, is it because software hasn't taken advantage of 64bit yet, or is it because we dont need 64bits yet?

Oh, and how did 8bit CPUs handle large numbers?
Thanks

 

[metalmackey]

tell first and people wont have to ask you

64bit isnt much faster because, put rather simply, it olny really allows bigger numbers to be used without having to split them up - which slows the process down conciderably becuase you have to process the larger numbers in seperate chunks.

With the transition from 8 to 16 bit you see an increase in the biggest number you can store as a whole from 255 to 65,535. moving to 32bit that increased again to 4,294,967,295.

As you can imagine a 64bit number it pretty damn large (18,446,744,073,709,551,615), and there arent many uses for numbers with that many digits which is why a lot of programs wont benifit from 64bit *as they are* unless totally rewritten with some heavy optimisation.

what it does do is overcome the memory limitation for 32bit cpus which is roughly 4gb. I'm sure that'll be useful sooner or later lol.

Thanks, cisnt more data being processed at once, which will be faster?

 

[metalmackey]

So its not possible for a 64bit cpu to process say 3 16bit numbers at the same time (1 cycle)?

 

[metalmackey]

So will 64bit be the max and only clock speeds and more cores going up? As 128bit CPUs will seem pretty useless.

 

[metalmackey]

Seems like developers have got it easy now, back in the 8bit days they had toovercome the limits. Now with all the SDKs like DirectX and 32/64bit big limits, a lot of the work is done for them.