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panicbutton wrote:

So, I have my Mac setup exactly how I wanted: MBP 2.4 C2D, 4GB RAM, BootCamp installed, 32GB partition for Windows XP Home... I think everything is good.

Now I have a Windows uber-geek friend of mine that tells me that I have to "tinker" with the boot.ini or config.sys or whatever - in order for my install of WinXP to recognize all 4GB of RAM.

Is this true?  I just tried searching the Microsoft KB and geez ~ a guy could get LOST in all that nonsense... I just did.  :-P

Thanks in advance for any replies.

-PB

If you don't want to dig in deep (and trust me, there's a crapload of digging that can be done, especially if Bat's posting ) the short answer is no, Windows XP cannot recognize 4GB of RAM, and will never be able to. If you really need 4GB of RAM, you need to obtain a 64 bit edition of Windows Vista.

Which is why Mac is so nice. who worries about addressing 4 GB on a Mac?

With PAE, however, a system can support up to 64GB of ram. 32 bit linux does this, as does windows server. For whatever reason, microsoft caps 32 bit Vista and XP at 4GB, when they can support much more.

I expect sturner installed 8 GB of RAM 'just because,' even tho he mostly uses his nice Mac for emailing and surfing here.

Next week, Mac Guy taunts PC Guy in a new ad campaign about how much more RAM he's got, and suggests Viagra.

General_K wrote:

Bat wrote:

I expect sturner installed 8 GB of RAM 'just because,' even tho he mostly uses his nice Mac for emailing and surfing here.

I don't need it, but I just upgraded my MacBook to 4GB. Because I can.

I haven't upgraded my macbook from 2GB to 4GB for one reason ...I won't be able to handle the fact that my 1000$ macbook out performs my G5 Pro 2.3D any more than it does already.

sturner wrote:

and I do all my gaming from Boot Camp cause that's where the games that I like are supported. Damn Windows stuff.

Heaven knows you're the only one hereabouts to game on Windows.

Booksley wrote:

If you don't want to dig in deep (and trust me, there's a crapload of digging that can be done, especially if Bat's posting )

...because I'm just that helpful.

As we have mentioned in previous articles, most modern system running in 32bit x86 mode have trouble seeing and using more than roughly 3GB of memory. This is because part of the total 4GB of memory space (not the physical memory) is reserved for various functions, such as computer components transferring data between each other using memory-mapped input-output (MMIO). The textbook example of this is the CPU transferring data to the memory of a video card, where a chunk of the address space equal to the size of the memory of the video card is reserved by the video card, and any data sent to those addresses actually ends up going to the video card. This design has many technical merits, but it makes the consumed memory addresses unavailable for use with physical memory.

Things only get more complex as we start including the operating system (in this case Windows) in to the equation. The above is actually handled by a combination of Windows and the BIOS, meanwhile Windows also needs some address space so that programs can communicate with the Windows kernel, for storing buffers, for storing memory tables, etc; all of which means we have lost even more address space. All of the above besides preventing us from addressing 4GB of physical memory are also the cause of the actual 2GB barrier that is the problem.

And more. From above, http://www.anandtech.com/showdoc.aspx?i=3034&p=2

Ribtorus wrote:

Implies a PC can't have a video card with more memory than the system RAM.

That's a config I would avoid, and fortunately one rarely seen, esp. in a home Win system. My rule of thumb is to only use big (as in local memory) videocards in systems with lots of system memory. A 512M card in a 2GB system seems copascetic in XP.