installed 4gb of ram but desktop shows 3.49gb

hi as title suggest, ive installed 4gb of ram which is detected on my bios, but my xp shows 3.49gb. my pcs dellgx620 3.2 dualcore the ram iu se is pc2 5300 type

thank you in advance

 

There is a lot of confusion about numbers because of the differences between binary and decimal notation. The nearest equivalent to 1000 decimal (in binary numbers) is 1024 decimal. Then there is the fact that if you do not have a Graphics card, the system may set aside some of your RAM for use by the display, and it may or may not report it as usable RAM. I suggest that you download and run Belarc Advisor, which will report the details of what is actually inside your machine

http://www.belarc.com/free_download.html

 

PeteC, I wasn't trying to explain how the op-system uses RAM, I was trying to explain why 1k and 1024 bytes could both be used to describe the same thing, and some of that confusion could contribute to the difference in reporting the size of installed RAM. That so-called 4 GB could actually mean 4096 MB, but the manufacturer could de-activate up to 96 MB to get rid of failing bytes. I'm not quite sure whether or not it would be visible to software reporting RAM size.

Seagate got sued and lost a big lawsuit because people didn't understand stuff like that. Seagate had stated a capacity for its drives, and some lawyers convinced a judge that it was not absolutely accurate.

 

If you were speaking about Hard Drives I'd agree with you but as far as RAM goes 1Gb is 1Gb ie 1024Mb or 1099511627776 bytes.

 

Sorry Wildlfire, but 30 years at IBM development labs assures me that memory cards contain a lot more bytes than are visible. It's not possible to make a perfect card, so they are made with lots of extra bytes, and built-in configuration maps to make the bad ones invisible. We had microprograms that could reconfigure the maps when a card failed in the field. The Microprogram could see the bytes that were not visible to the software. The process is similar to that used by discs to avoid unusable tracks and bad spots on the magnetic surface. In any case, the goal is to sell the usable capacity, regardless of actual size.

I've been out of touch for years since retirement, but I'm pretty sure things haven't changed much.

 

I won't get involved in a slanging match here, all I'll say is when you buy 1GB RAM that is what you get. With my 26 years computer experience I have never found this not to be the case.

 

911, we understand what you're saying but I think your post is a bit misleading because what you're saying has ABSOLUTELY nothing to do with the fact that 32-bit Windows cannot address the full 4GB of RAM and is the reason that Windows reports having the lesser amount.

Last time I checked I think it was even less than 3.5GB, eh?

Mikeapple, if you want, you can google "3GB switch" or "PAE switch" and you can give Windows the ability to use your 4GB more efficiently (if that's the right word).

I used to use the 3GB switch. It caused some little 3rd party apps to crash so I kind of let it slide. I should probably try it again as things get updated. The best way to handle it is to set up a dual-boot, one with the 3GB switch and one without and test your apps accordingly.

BTW, I think I rememember an MS article stating that the 3GB switch could be used in WinXP Pro but not WinXP Home, not sure tho.

 

That depends on the system and what address space other resources require.

The 3GB Switch will not help in Mikeapple's case.

 

None of this is helping mikeapple who didn't complain that Windows couldn't address all his RAM, but that he was getting a report that he had less than he thought was installed. I wasn't trying to mislead anyone by explaining that there are different ways to describe the same amount of RAM, and I thought that might be part of the problem.

But:
I'm done here.

 

Mikeapple's problem has been explained and he is in an unfortunate position but other than upgrading to a 64bit system there's nothing he or we can do about it. This problem arises quite often because computer stores do not fully inform the customers. When I worked in such a store if customers asked for 2gig or so of memory I advised them of this problem (against managment instructions), in fact we were even told to install the memory knowing this would happen.

 

Just to lighten things up here: Anyone remember the 640KB barrier and the Upper Memory Area between the 640kb and 1024kb? Isn't this, in essence, the same principle?

Now, at this point, is this where PAE may come into play or do you have to have above 4GB for PAE to be an option?

 

Actually I was about to say not really, but yes it is very similar, using quem and later ms memmaker you were able to access some of that high memory but it was still limited due to devices and ROM needing address space.

PAE may help if you have around 3GB, with 4GB it won't.

I blame Bill Gates, "no one will ever need more than 640Kb memory ". Yeah Right

 

WildFire, what do you know that I don't? I have 4GB using WinXP Pro 32-bit. Should I not use the PAE switch? You're implication is that it won't "help ". Can you elaborate on that?

 

Read this

Particulary...

Edit: I should point out that this is only applicable to 32bit systems and does not apply to 64 bit OS's

 

Well I read that, like I have many articles on the subject...most of which were totally confusing.

But I did find this article - which actually seems to explain it quite clearly.

To summarize it, in a 4GB 32-bit Windows OS, you get 2GB for user space and 2GB for the OS. Using the PAE switch, you get 3GB for user space and 1GB for the OS. But your app needs to have been compiled with the /largeaddressspace switch or else it will not take advantage of the "extra" memory space. And, if you do it you can cause some serious issues because your OS and all its "stuff" only has 1GB to work in.

They mentioned one specific scenario where the PAE switch is recommended (actually required):
"is with Microsoft Exchange servers that house public folders and / or mailboxes. "

It sounds like, for many users, this switch should be just forgotten about.

 

No, I'm too old to get insulted by anything or anyone.
I just figured that the thread was not going anywhere useful, so there was no reason to keep on with it.