2gb vs 4gb

Just wondering if yall think its worth it to upgrade from 2 to 4. Are there any reviews or benchmarks? thanks

Hp dv6646
Amd turion64 tl-58 1.9
2gb ram
nvidia 7150m

 

What's your OS? Is it 32bit or 64bit?

 

It's worth it if you have a 64bit OS. If you don't have a 64bit operating system, you will not be able to recognize 4gb of RAM. This has been discussed a countless number of times on this forum, just search for it.

 

Oh yeah sorry I have a vista 64bit.

 

I know about the whole recognizable thing I was just wondering if it would be worth it.

 

What apps are you running? Are you seeing HDD hits a lot other when you first open application? If so yea it will help if not then won't help, but won't hurt either.

 

Emphasized for clarity.

 

So your saying it will help only if you have to access the hard drive alot?

The apps i run are itunes which is pretty slow, many games, and some dvd decoders.

 

Just get 4GB. Memory is cheap, everything will run smooth, and you won't be complaining ever again about RAM slowing you down (for a very long time). End!

 

Well, with 64bit OS, you'll be able to use all 4GB; however, you may not see much of a gain from 2GB to 4GB. Depending on your budget, you may find that prices are low enough that you may want to go ahead and go for 4GB. That'll be better for multitasking.

 

Note, even with a 32-bit OS, since RAM is so cheap, it is still worth it.
3.5GB > 2GB.

The difference is $70, and that's provided you don't sell your old 2x 1GB sticks.

 

Can Vista 32 bit effectively use 3.2GB or 3.5GB?

 

MS documents say 3.2GB Max. Many have posted they get 3.5GB. Some don't even get 3GB.

 

I'm sure it will also depend on if the GPU is using some of the RAM? Mine says I have 3.5GB (Desktop w/XP and 4GB RAM). I'm with Panic, that's still more than 2GB.

 

note its 4GB addressable...

Meaning your graphics RAM, reserved RAM, and other hardware takes from the 4GB limit.

There is another problem and that is that windows divides your RAM into two pools and only ever plays with a max of 2GB unless you toss the 3gb switch for larger programs.

If you want to make accessible 3GB RAM for larger applications in Windows Vista, use BCDedit.exe (boot configuration data editor).

bcdedit /set IncreaseUserVa 3072


to disable

bcdedit /deletevalue IncreaseUserVa

(note to run this you require a command prompt in admin mode)

 

The fact that Vista sees 3.5GB does not have to mean it is using 3.5GB.

Ofcourse 3.2GB is still nicer than 2GB.

 

I'm sure it's not, as well as 64bit sees 4GB, doesn't not have to mean it is using 4GB.

Of course 4GB is still nicer than 2GB.

 

I have no clue what are you are meaning to say.

Are you saying Vista 32bit can use more than 3.2GB?

 

I followed your analogy with the same analogy; I see it has the same effect on you as yours did on me.

I'm saying my XP system sees 3.5, what it uses is in the air.

If I share 512mb of memory with the video card, and windows show me to have just under 3GB, then how much RAM do I really have?

 

'What it uses is in the air', does that mean you don't know?

(english is not my native language)

 

My mom is German, so I feel your pain.

You said it might see 3.5, but doesn't mean it uses 3.5. I'm saying...if it's showing 3.5 before the shared GPU memory, and 3GB afterward adding shared memory for the GPU (512mb). The math tells me, it's using the 3.5 effectively.

 

Right now it is safe to say unless Vista SP1 what the OS shows is what it can use (XP also). I don't know what MS says about XP but regardless there are people who see more than 3.2GB with Vista.

RAM is cheap putting 4GB in 32bit OS is not the biggest waste as long as the person understands some won't be used. I think 3GB is the most economical but well I am cheap.

 

Where does it show 3.5GB?

Edit: just noticed you are using XP. never mind. I was interested in the maximum memory for Vista 32.

 

March 08, 2007
Dude, Where's My 4 Gigabytes of RAM?

Due to fallout from a recent computer catastrophe at work, I had the opportunity to salvage 2 GB of memory. I installed the memory in my work box, which brings it up to 4 gigabytes of RAM-- 4,096 megabytes in total. But that's not what I saw in System Information:

Vista System Information, 4 GB installed, 32-bit operating system
Only 3,454 megabytes. Dude, where's my 4 gigabytes of RAM?

The screenshot itself provides a fairly obvious hint why this is happening: 32-bit Operating System. In any 32-bit operating system, the virtual address space is limited, by definition, to the size of a 32-bit value:

As far as 32-bit Vista is concerned, the world ends at 4,096 megabytes. That's it. That's all there is. No más.

Addressing more than 4 GB of memory is possible in a 32-bit operating system, but it takes nasty hardware hacks like 36-bit PAE extensions in the CPU, together with nasty software hacks like the AWE API. Unless the application is specifically coded to be take advantage of these hacks, it's confined to 4 GB. Well, actually, it's stuck with even less-- 2 GB or 3 GB of virtual address space, at least on Windows.

OK, so we're limited to 4,096 megabytes of virtual address space on a 32-bit operating system. Could be worse.* We could be back in 16-bit land, where the world ended at 64 kilobytes. Brr. I'm getting the shakes just thinking about segments, and pointers of the near and far variety. Let us never speak of this again.

But back to our mystery. Where, exactly, did the other 642 megabytes of my memory go? Raymond Chen provides this clue:

Ian Griffiths offers a more detailed explanation:

For a long time this wasn't a problem, because there was a whole 4GB of address space, so devices typically lurk up in the top 1GB of physical address space, leaving the bottom 3GB for memory. And 3GB should be enough for anyone, right?

So what actually happens if you go out and buy 4GB of memory for your PC? Well, it's just like the DOS days - there's a hole in your memory map for the IO. (Now it's only 25% of the total address space, but it's still a big hole.) So the bottom 3GB of your memory will be available, but there's an issue with that last 1GB.

And if you think devices can't possibly need that much memory-mapped IO, I have some sobering news for you: by this summer, you'll be able to buy video cards with 1 GB of video memory.

To be perfectly clear, this isn't a Windows problem-- it's an x86 hardware problem. The memory hole is quite literally invisible to the CPU, no matter what 32-bit operating system you choose. The following diagram from Intel illustrates just where the memory hole is:

The proper solution to this whole conundrum is to use a 64-bit operating system. However, even with a 64-bit OS, you'll still be at the mercy of your motherboard's chipset and BIOS; make sure your motherboard supports using 4 GB or more of memory, as outlined in this MSKB article.

264 = 18,446,744,073,709,551,616

18,446,744,073,709,551,616 / (1,024 x 1,024) / 8 = 2 exabytes

In case you're wondering, the progression is giga, tera, peta, exa.

Although the performance benefits of 64-bit are somewhat dubious on the desktop, a 64-bit OS absolutely essential if you run applications that need to use more than 2 GB of memory. It's not common, but we're getting there.

The memory hole for IO still exists in the 64-bit world, but most modern BIOSes allow you to banish the IO memory hole (pdf) to some (for now) ridiculously high limit when you're running a 64-bit OS. Don't get too excited, though. The user-mode virtual address space in 64-bit Windows is a mere 8 terabytes. Suffice it to say that we won't be running out of physical or virtual address space on 64-bit operating systems for the forseeable future. It's the final solution, at least for the lifetime of everyone reading this blog post today.

Here's one parting bit of advice: if, like me, you're planning to stick with a 32-bit operating system for the next few years, don't waste your money on 4 GB of RAM. You won't be able to use it all. Buy 3 GB instead. Every motherboard I'm aware of will happily accept 2 x 1 GB and 2 x 512 MB DIMMs.

* Could be raining.


original article: http://www.codinghorror.com/blog/archives/000811.html

 

Damn. That is one hella good article/post. Thanks, mate.

 

Regarding the dual channel aspect:

http://forum.notebookreview.com/showthread.php?p=3723021