Windows XP can only recognize a little around 2 gigs, if I recall. I don't know how much a 64 bit OS can recognize, but I do not believe its anywhere near 16 gigs.

On multithreading: Yes, multhreading isn't as simple as an option in the .ini. The program must be created with multi threading in mind, as you have to assign threads to certain operations, etc etc.

For 64-bit windows 7 home premium the max usable is 16GB, but for win7 professional supports up to 192GB RAM.

I got the RAM only because I need it for working with extremely large files in Photoshop, After Effects, etc. Most applications and games don't use very much.

XP x64 (all editions) supported up to 128GB of physical RAM, the theoretical limit of the 64bit architecture is 16 exabytes. Any 64bit OS can handle 16GB of RAM in its sleep - your motherboard, however, may not.

Of course, XP x64 is rubbish and should be avoided.

That's because most games are programmed for 32-bit systems (the so called x86 architecture) and not for 64-bit systems for maximum availability. 32-bit programs can be run on 64-bit systems, but not the other way around. That's why gamedevs are avoiding 64 for such a long time - they don't want to limit their audience. One of the implications of programming for 32-bit systems is that you can only use at most 4 GB of RAM because that's how much a 32-bit address can cover. (to better understand this, calculate 2 to the power of 32, then divide by 1024 for KB, then again for MB and finally again for GB - you'll get exactly 4 GB). Since the addresses in the programs are hard-wired to be at most of that length, they can't use any more memory by definition. When 64-bit games become mainstream, they'll be able to use a whole lot more (two to the power of 64, baby).

The thing about developing for 64-bit is (apart from the lack of backwards compatibility) that you're building it expecting large quantities of RAM. APB did this, performance on 32-bit systems was a joke when compared to 64-bits. That being said if you're running with a 64-bit CPU and enough RAM then the game (Skyrim) should take advantage of that.

I'm not sure I follow this I thought that by the time the game is ready for release Xp wouldn't be supported anymore so why would Bethesda develop for an obsolete architecture?

I'm running a 6 core AMD on Win 7 64 - if Skyrim comes out as 32 bit does this mean I'll need to run the 4gb patch on it?

Hopefully. PS3 has seven of these bad boys. Cell processor can do some serious shredding of whatever you throw at it.

Is it possible that there is some multi-threading optimization built in even if the game were coded for 32-bit systems?

Or is it most likely that Skyrim will be coded for 64-bit in order to optimize multi-threading (and as a result allowing the game to make efficient use of large amounts of ram in excess of 4GB )?

The first question: Windows XP is not an architecture, it is an operating system build on top of an architecture. The term "architecture" describes your motherboard and processor. Since almost all PC games are based on DirectX, the OS doesn't matter, give or take a few performance variations. The only OS restriction is that MS won't let you have DirectX 10 or higher on XP (which is really just a marketing gimmick).

Second question: No. To my knowledge 32-bit games (and programs in general) should work on 64-bit architectures out-of-the-box.

Multithreading and 64 bit architecture have nothing to do with each other, and unless you're writing at a very low level you probably don't have to do anything to compile your executable for both 32 and 64 bit architectures.

I saw improvements from running the 4GB patch on New Vegas and Oblivion

@Eps - Illuminiel is referring to this patch

http://www.ntcore.com/4gb_patch.php

Sigh. You need to brush up on your nerdness :nerd: because that was a rather stupid question.

The number of bits in an architecture has nothing to do with threads. It simply describes the smallest amount of data that a processor core can process in one of it's millions of cycles. The more data per cycle, the better the overall processing power.

Threads aren't dependendant of this or the number of cores for that matter - multithreaded programs can run even on a single core, though naturally there isn't as much of a benefit as running them on multi-core systems.

Oh, and by the way, the number of cores isn't dependant of the number of bits either. There are dual-core 32-bit processors. It's simply coincidence that 64-bit systems and dual-core systems started being used on a large scale at the same time.

Listen honey, the PS3 could do some serious shredding of whatever you could throw at a mid range gaming pc in 2006 - but times have changed. It's 2011 now, and Skyrim on consoles will be destroyed by the PC performance (unless it's badly optimized by Bethesda).

Now now, lets not go overboard. I have an I7 950 @ 4.2GHz and I want the game to fly!! (6GB 1600MHz RAM @ 7-8-7-20, Crossfired 5870s, SSD.)



XP has support until 2014.

I see. This is a an OS thing, a limitation imposed for the sake of optimization. And yeah, it's well possible you'll have to use it. I can't imagine Skyrim reaching it's full potential with just 2 GB.

Sorry - I meant the 32 bit architecture that Xp runs on

Am sure Skyrim as a 32 bit will run just as well as Morrowind does on my system - however I was just confused as to why Skyrim would not be designed for Win 7 which I suspect most users select the 64 bit version of

Would it be possible to patch x86 executables in order to let them have 8GB (or more) of virtual memory on x64 platforms, in the way that the NTCore increases the amount from 2GB to 4GB?

Yes. It's just a flag that needs to be set.



Which is strange, since Skyrim is a big game with a lot of data to handle. To me it seems counter-productive to not use up more RAM if it's available.

No. As I have stated before, x86 (32-bit) executables can't use more than 4GB even in theory. That's the hardware limit.

It has to fit into 512MB of RAM, so don't go expecting it to need to be a 64bit executable, unfortunately ;(

I certainly hope so, this laptop is surprisingly powerfull, but most games aren't taking advantage of Quadcore CPU's which means my machines power doesn't make any difference.

It's a choice of more sales or a better game. Many people (myself included) still have 32-bit PC's from about 5 years ago. You either cater the game for more customers (x86) or you create a masterpiece that only a limited audience can enojy (x64).

There's really nothing stopping them from shipping two executables, you know?

Nope, most software these days does it, it's mostly the game industry that keeps lagging behind.

Yes, you are correct. Did some googling and it's not that easy. Somebody else explained it like it was a flag that needed to be changed and the program would be large address aware.


I know hat you mean. APB was codded for x64 mostly and although it ran on 32-bit systems the fact that the game would need more ram than what 32-bit could offer meant they had to scale it down qutie a bit on those systems. Really shines on x64 though.