Do we need more RAM with a 64bit CPU? Options

[amir]

I've been reading about 64bit CPU for a while & i got to sth weird on Wikipedia.

Theoretically, some programs could well be faster in 32-bit mode. Under some architectures, instructions for 64-bit computing take up more storage space than the earlier 32-bit ones, so it is possible that some 32-bit programs will fit into the CPU's high-speed cache while equivalent 64-bit programs will not. In basic terms moving 64 bits at a time to perform otherwise 32 bit work simply requires more processing effort to/from memory

The main disadvantage of 64-bit architectures is that relative to 32-bit architectures the same data occupies slightly more space in memory (due to swollen pointers and possibly other types and alignment padding). This increases the memory requirements of a given process and can have implications for efficient processor cache utilization

Does this mean i need 1024 MB of RAM to work as 512? Or only if i use a 64bit version of windows? Or only if i use a software written for 64bit cpus?

I'll appreciate if someone shed some light here!

[usr.c]

Sorry to leave you hanging for so long amir. Unfortunately, my reply isn't going to help much since it's just a cry for help:

ThGreenMofo, where are you?

[amir]

I'm still looking for some clear info on this but the more web sites i check, the more confused i get.

[j-rah]

just so happened to come across this article from ZDNet news about 64bit chips. There are a couple of paragrpaghs about memory in there too.

Hope it helps.

[ThGreenMoFo]

Hey everyone... it's been awhile - I've been out in Japan for the last few months.

In any event - Amir,

I really have no idea what that Wikipedia article is talking about. To my understanding, current "32-bit" processors have internal 64-bit buses but a 32-bit input bus (effectively reducing the processor to 32-bit). At least with the original 64-bit processors (AMD FX series) I was under the assumption that the external CPU bus had been increased from 32- to 64-bits - making the CPU a "true" 64-bit processor. Basically what has happened is that the bottleneck between the system buses and the CPU has been opened up.

As far as what I got out of that article, if you put 1024 MB into a system containing a 64-bit CPU, it's still going to show up during POST as 1024 MB. The only thing that I think it's saying is that a program designed specifically for a 64-bit processor will take up more space in memory than a traditional 32-bit processor.

If you think about it this sort of makes sense. The speed of the 64-bit processors are comparable to 32-bit processors (usually a little slower clocked) but you've basically doubled the amount of information you're taking in (and hypothetically) processing i.e. you should have double the output of information from the CPU needing to be stored in memory for system retrieval so you're taking up more space.

I don't know if this is correct but it's my best guess. Personally, if you were/are thinking about purchasing a 64-bit CPU - I wouldn't, unless you are doing some serious graphics/video editing/production (in which case you're going to probably want more than a gig of RAM anyhow). Keep in mind you're going to need Windows XP x64 in order for the OS to take advantage of the 64-bits and that, like the article said, any 32-bit program is going to be emulated (theoretically reducing its speed). My personal feeling is that it's still too early to adopt the 64 bit CPUs for home use - they're currently comparatively expensive and don't offer the user much of an advantage over a traditional 32-bit based CPU.

[amir]

Thanx for the info
Although i have already done my shopping for a new CPU (32 bit) but it sounds like AGAIN unaware users are being abused this time by Intel/AMD & they are being convinced to go for 64bit no matter what they want to do with their PCs. I was wondering if anyone would still buy 32bit second hand CPUs 2 years from now 4tunately my tight budget made the decision for me!

[ThGreenMoFo]

I think you hit the nail on the head. There will always be early adopters though.

Glad to hear you stuck with the 32-bit CPU. In my opinion I think you'll be set with it for at least another couple years.

I ran into this a few minutes ago -

http://www.anandtech.com/cpuchipsets/showdoc.aspx?i=2411&p=3

It reportedly shows the difference in graphics between a 32-bit and 64-bit processor on the game Farcry after the application of 64-bit patches. If you mouse over the images youll see what it looks like in 64-bit. To me, it looks like all you really get is some added textures and shadowing effects - hardly worth completely revamping all your system components for (at this time).