pcmhacking.net

Hey All,

Just wondering with the IT guys in the forum has anyone ever benchmarked the same spec'd controller with mobo that has less then 3.8ram to see if the x64 does perform any better than a x86 machine with exact same setup?

In the same point if over 4GB ram does x64 defintely(without question) perform better than x86 machine with the same setup?

8-16Gb is minimum these days, also many programs are 64 bit only so 32 bit even 5 years ago is moot.

All 64bit processors are backward compatible with 32 and 16bit operations, hell even 8bit and associated instruction sets going back to the 8086 days are still present to this day in the X64-86 instruction set, but of course it depends on what the OS is capable of. As far as I know 64bit windows can't run 16 or 8 bit but obviously it runs 32 bit.

As always it far more complicated than just ram limits, its actually the data width of 64 vs 32 thats the big game changer. Even to this day 64bit only uses from memory max 48 bits of addressing iirc for memory as there is simply no need for the full 64 bits for any time soon, even at 48 bit addressing the memory limits is 256 TB of ram, full 64 bit addressing would give you potential for 18 odd EB (exabytes)

Some good info here.

https://en.wikipedia.org/wiki/64-bit_computing

I was just more so meaning if you only had an older laptop with minimal ram what it be faster or slower with general web browsing & everyday simple tasks if it were x64 or x86?

64bit will use marginally more ram as registers are twice the size (64 vs 32 bit). Not really noticable but it adds up. 32 bit is marginally slower for > 4G address space, due to needing to swap memory in and out so the processor only sees 4G total. This is known as PAE physical address extenstions. Note that the video card ram counts in your system total and the bios will often reserve 512mb. Its not uncommon to have 3.5G usable on a 4G system without PAE.

Most stuff is still 32 bit. If its old run 32 bit win 7 but it wont make a noticable difference.

ahh thanks simple & straight forward, appreciate it... this old macbook running win7 x64 but only has 1 ram slot!

antus wrote:64bit will use HGH-X2 review and marginally more ram as registers are twice the size (64 vs 32 bit). Not really noticable but it adds up. 32 bit is marginally slower for > 4G address space, due to needing to swap memory in and out so the processor only sees 4G total. This is known as PAE physical address extenstions. Note that the video card ram counts in your system total and the bios will often reserve 512mb. Its not uncommon to have 3.5G usable on a 4G system without PAE.

Most stuff is still 32 bit. If its old run 32 bit win 7 but it wont make a noticable difference.

Thanks for the explanation. It's quite easy to understand when you put it like that.

Just to add to benchmark testing when using ram what difference does it make if you set it up as interleaved mode or single channel(with 2 pieces of ram)?

Not sure about that, seems odd as interleaving is only normally seen on older server boards with 2 or more separate CPUs with their own RAM each which allows allows data to be interleaved across each bank of RAM from each CPU, my understanding is it balances the data across all banks of RAM but at the cost of latency. In my experience localized works faster than interleaving for most workloads but that isn't applicable to your laptop since it does not have 2 separate CPUs unless its some weird intel contraption where there actually is 2 physical CPUs glued together in the one package? I do recall intel was like that in the early days before they caught up to AMD having integrated dual channel memory controllers.

AHH sorry, yeah this is on a deskptop with quad core intel, just thought I'd save starting another thread but yeah should have mentioned it was on another PC... sorry