3GB vs. 4GB

[W4HDM]

I am getting ready to submit an order for a laptop (XPS M1330) with this set up:

Intel Core 2 Duo T8300(2.4GHz, 800Mhz, 3M L2 Cache)
3GB, DDR2, 667MHz 2 Dimm
128MB NVIDIA GeForce 8400M GS
200G 7200RPM SATA Hard Drive Free Fall Sensor

I originally had chosen the 4GB, DDR2 and after a review from a service tech at the company they gave this advice.

"The operating system can only address about 4 GB of allocated memory (this is a limitation of the 32-bit architecture). Allocated memory is made up of physical RAM and any I/O space needed by devices (the system “remembers” BIOS, video cards, motherboard resources, chip set, etc). Normally this is not a problem, but when a system has 4 GB of physical memory installed, the need for I/O space takes precedence, and the amount of RAM visible to the operating system is limited to 4 GB minus the I/O allocation (which is usually about 1GB), so you will only see 3GB or so of available RAM. I have 4GB on my desktop and Windows only sees 3.25GB – so it’s not really worth the extra $200 to get that ¼ GB, when you can get the other features that will help you out better…"

Can I get a second opinion from someone on QRZ please. Why would they give the option if it is not necessary? More money for them?
If I stick with the 3GB will it only see 2.25GB?

Thanks in advance.

[KB1PLB]

I have never heard of a computer with 3gb.

If I were in your position I would only buy a PC with dedicated video memory so the ram is used for processing and not shared with video. Good luck.

73

[KE5SCY]

I haven't heard of this myself, but I will definitely check into it for you.
You would see 3 if you had 3.
We have computers at my high school that have 3, and it shows 3.

Definitely look for something with a dedicated video card though. That makes a HUGE difference!

[KI4ZSQ]

$200 for an extra stick of 2GM memory?

Edited... laptop 667, sorry my bad... still much much less $:

http://www.newegg.com/Product/Product.aspx?Item=N82E16820211200

they are overcharging you... worth it to get the extra memory in my opinion if they offered it at a reasonable price.

[KD6NIG]

You'll see less available because the onboard "video card" will take some (likely 128 or 256MB) and when you look in Windows it will report it as 3.8GB or something similar, not 4GB.

I think you're being told that to avoid a call after you get it saying "I asked for 4, its only showing 3!"

Windows will report the amount of ram available to it minus whatever the internal adapter takes in Control Panel/System.

Its legit if thats the reasoning.

But, if it takes more than what the video card would take (unless, of course, it takes a gig!) something is fishy about the mobo. Yes, you can get systems and put more ram in them than they can take, but if thats the case, I would wonder why they even have 4GB as an option if it won't work.

Seeing that your specs show 128MB, its probably a motherboard issue-meaning it can't address more than that. The question of 3GB showing less would have to be asked of the tech, or you'd have to get the motherboard numbers and see for yourself on the specs.

And, 3GB is an odd combination. Usually, ram doubles in steps, so you'd start at 8, go to 16, 32, 64, 128, 256, 512, 1GB (~1024MB), 2GB, 4GB. It is POSSIBLE to have odd arrangements (ie, you could put a 1GB and a 2GB in and have 3GB provided the motherboard could support it) but its usually recommended that the ram "match up" (IE, if you have 2 ram slots, you'd put 2 of the same in, with 4, four of the same) not only in size but in speed (ram does have MHZ speeds as well, mixing slower ram with faster means they ALL go the slower speed, usually).

I'd find it odd that if the motherboard can only address 3GB that they would offer 4GB as an option.

How much of a cost difference are you looking at? Me personally I'd go with the 4GB so they would match up, but it depends on the motherboard. It does sound funny and you are right for wondering about it.

It could also be that the ROM (read only memory) copies to RAM when the computer starts. Thats possible, but 1GB is a lot of space for that. Unless hes referring to the space the OS takes, but even that space is visible as being part of the ram available to Windows, its just "taken up" when Windows is running, obviously.

The way the email is worded is funny, and too technical for the average user. A clearer explanation that is probably logical could be given, but its also kinda vague.

The stuff that they are claiming as overhead should be on ROM and should be readable from there. 1GB for all that sounds a bit high. Sure the OS and stuff will take up space when its running. But total reported available ram shouldn't be affected by that.

It sounds odd. Unless it copies that stuff to RAM for speed, maybe. That could be what its doing... in which case 4GB would give you 3GB avail, and 3GB installed would give you 2GB avail, roughly.

Must be a motherboard "feature", is all I can think of.... Legit? Probably. Odd? Yep.

But 1GB for I/O is awfully high, also. Thats what sounds really strange. I know my home computer (a Dell) shows 3.8 GB available out of 4GB because of the video card internal, but I don't have any taken for I/O.

The only thing I can think of is the motherboard can only address 3.2 GB, but thats odd in itself. The email is confusing. If the system has to take the ram to operate, it should take it in every configuration of ram. But hes suggesting to save $200 and get 3GB and then it won't be taken, if thats the case, then the explanation of why its taking it is misleading (for "I/O").

Thats the part I'm not getting, and I've been around computers for years. Either it takes that amount of ram and uses it "for I/O" or it doesn't support more than 3.2 GB. Thats the only logic I can deride from that email.

Neither of which make sense to me unless its an odd motherboard. Which, seeing some of the stuff I've seen is possible, but I've never seen a GB reserved for I/O operation. For BIOS mirroring and for video, yes. Its an odd way to put it and the first time I've seen it put that way, definetely.

[KD6NIG]

I have never heard of a computer with 3gb.

If I were in your position I would only buy a PC with dedicated video memory so the ram is used for processing and not shared with video. Good luck.

73

I'd suggest that too but nowadays most laptops have integrated video to save space :) The Apple "thin" laptop is a great example of that :)

[K1MDC]

That's not how modern computers work. What the tech told you was true 20 years ago. Modern machines and OS's use memory management units to allow access to much larger amounts of RAM. Any single process on your machine will only have access to 4gb, that's a limitation of 32 bit registers. Each process, including the OS, can have its own 4gb block, though.

Matched memory sticks, btw, mean pretty much nothing to most users. There is a slight benefit to users with graphics cards with large AGP apertures, but only for applications that use direct memory access.

[w8gtf]

That's not how modern computers work. What the tech told you was true 20 years ago. Modern machines and OS's use memory management units to allow access to much larger amounts of RAM. Any single process on your machine will only have access to 4gb, that's a limitation of 32 bit registers. Each process, including the OS, can have its own 4gb block, though.

Matched memory sticks, btw, mean pretty much nothing to most users. There is a slight benefit to users with graphics cards with large AGP apertures, but only for applications that use direct memory access.

Actually, computers can handle 4 gigs, but Windows XP can't. Sometimes you can tweek XP to see 3.5 gigs of ram. We actually tried this at work when we couldn't figure out why our boxes only showed 3 gigs of ram when 4 gigs were actually installed.

This is due to the way Windows XP handles memory addressing. I believe that Windows Vista has the same issue. If you doubt that the problem is with Windows, grab your favorite Linux Live CD (I perfer SLAX), and boot your computer with it. Don't worry, this won't affect your computer.

When SLAX is booted off of a CD, it views your hard disk in read only mode (unless you configure it otherwise). When you are done, just shut down and restart without the live CD in. Also, you can check your BIOS and it will tell you that you have 4 gigs installed when infact Windows see's less.

Basically, to get around this you need to upgrade to 64bit version of Windows (XP or Vista).

As for odd combinations of ram. Because of this sitution, some manufactures are only putting 3 gigs of ram in boxes. I'm looking at a media center PC that has two 1 gigs sticks and two 512mb sticks of ram.

[KD6NIG]

That would be a more logical explanation than the one he got initally. :)

I wonder if Dell modified my XP then, because it shows 3.8, I swear..... I'll have to check it out when I get home. I don't think its 64 bit but I could be wrong. :)

You would have thunk they would have fixed it in Vista. Good way to get people to pay extra for 64 bit though :)

[w8gtf]

That would be a more logical explanation than the one he got initally. :)

I wonder if Dell modified my XP then, because it shows 3.8, I swear..... I'll have to check it out when I get home. I don't think its 64 bit but I could be wrong. :)

You would have thunk they would have fixed it in Vista. Good way to get people to pay extra for 64 bit though :)

Here's an article I found on HP's site that explains it.
http://h10025.www1.hp.com/ewfrf/wc/genericDocument?docname=c00612217&cc=us&dlc=en&lc=en&jumpid=reg_R1002_USEN

According to the article, this affects all 32 bit versions of Windows.

[W4HDM]

Thanks for all of the input guys! I remained confused until the link came out. It seems 4G would have been better, but I suppose I could live with out it. I took the money I saved and put it toward more useful options. I can always change the ram later; like you said .. for less money than they wanted. Now the hard part .......... the wait

[WA9SVD]

Almost ALL (if not all) laptops will have video integrated on the MoBo and use part of system RAM for video purposes, although the actual amount of memory will vary with different models/brands.

But regardless of the amount of system RAM installed, the amount Windoze reports will always be less than the amount actually installed, because Windoze does not count the memory used by the video system. Thu, if the machine dedicates 256 MB to video, a machinw with 1 GB will have 768 MB reported by Windoze, a 2 GB machine will report 1,768 MB, and so on.

But typical prices for 1-2 GB laptop memory are running $30-$70 dollars (Kingston) so $200 for the extra memory is exorbitant. On most laptops, a memory transplant is easier and faster than on a desktop.

[W4HDM]

Thanks Larry,

I think I made a good decision then. I can upgrade once I get the system. I also found Dell to overprice their accessories as well. For example a backpack for the laptop runs 69.99 on Dell's site and I saw it in Fry's yesterday for 40.00! There are probably some other items I should have held of on as well, but live and learn.

Here is what I got for those interested.

Item Number Quantity Item Description

223-6992 1 XPS M1330, Intel Core 2 Duo T8300(2.4GHz, 800Mhz, 3M L2 Cache)

311-7638 1 3GB, DDR2, 667MHz 2 Dimm

320-5583 1 13.3 Inch Wide Screen WXGA TL WLED Backlit LCD with Camera, XPS M1330

320-5603 1 128MB NVIDIA GeForce 8400M GS, for XPS M1330

341-6252 1 200G 7200RPM SATA Hard Drive Free Fall Sensor

420-6815 1 Microsoft Windows Vista Ultimate 32-bit Edition English,Inspiron

420-7098 1 Media Direct 3.3

420-5769 1 Internet Search and Portal

412-0946 1 Dell Travel ExpressCard Remote Control, IR

310-9246 1 Creative Earbud EP630

420-7468 1 ADOBE ACROBAT READER 8.1 DIM/INSP

313-5361 1 8X DVD+/-RW Slot Load Drive for XPSM1330

313-4783 1 Integrated High Definition Audio 2.0

430-2589 1 Intel 3945 WLAN (802.11a/g) Mini Card

312-0561 1 56 WHr 6-cell Lithium Ion Primary Battery, for XPS M1330

420-6588 1 Microsoft Office 2007 Professional Edition

986-3557 1 LoJack Theft Recovery Service - 1 Year

410-1196 1 Adobe Pepe,English

310-9273 1 Fingerprint Reader

430-2566 1 Dell Wireless 355 Bluetooth Module (2.0+EDR) w/ 4 port wireless hub

430-2692 1 Dell Wireless 400,Ultra Wide Band

320-5771 1 Slim and Light LCD with TuxedoBlack Casing and Camera XPS M1330

310-9348 1 Intel Centrino Core Duo Processor

Edit to shorten the list Warranties, ect.

Thanks

[K1MDC]

Almost ALL (if not all) laptops will have video integrated on the MoBo and use part of system RAM for video purposes, although the actual amount of memory will vary with different models/brands.

Not the machine that he's getting. It doesn't use integrated chipset video like a lot of laptops. It's got a PCI-X slot with a real video card with it's own memory.

[WA9SVD]

Not the machine that he's getting. It doesn't use integrated chipset video like a lot of laptops. It's got a PCI-X slot with a real video card with it's own memory.

From his description, he chose the option of the added video card.
IMHO, a good choice. And memory can easily be added, with Vista it WILL be desirable. Fry's, Staples, Office Depot, Best Buy and Circus City typically have good sale prices on the memory, so adding to the max shouldn't be a problem.

A rather impressive list of features.

[KD0DKI]

Windows XP Pro 32bit can see 4gig of RAM but there is a setting in the Boot.ini file that must be made.
But 4gig is not what will be allocated to the user, only 3gig will be allocated to the user. The other memory will be allocated to the XP.
To use 4gig of RAM and have some of it user allocated you would need a 64 bit OS like XP Pro 64bit or Vista 64bit on the windows OS.
Most of the Linux vendors have 64bit versions, this goes for UNIX and BSD as well.
If you are going to run a 32bit OS just go with 3 gig of RAM the setup of the boot.ini is not difficult see this.

http://support.microsoft.com/kb/291988/en-us

[KD5GKE]

Here is a good read on why there is a 3GB barrier with 32 bit arch. It's due to historical reasons, and I found this to explain it well:

http://www.dansdata.com/askdan00015.htm

[KE5SCY]

Here is a good read on why there is a 3GB barrier with 32 bit arch. It's due to historical reasons, and I found this to explain it well:

http://www.dansdata.com/askdan00015.htm
Thanks for finding that, I think it did explain it well!

[KD0DKI]

I'm not sure the article is as accurate as it should be.

The machine will use the 4gig of RAM and Windows XP will use it if configured to do so. But RAM after 3gig will be allocated to XP not the user environment.
I've run XP 64bit it is faster and more stable then XP, but forget using some applications that were not written as 64bit. If it addresses hardware you will have issues, if the installer makes a 16bit call the software will not install. There are many issues with XP 63bit that are not easy to over come it you don't know what you are doing.


Sam

[kf6rdn]

Dell XPS Laptops are excellent, I have the 1210 one, ALOT of power in a very small package.

YES the video is integrated, with it's own memory.

I've thought about upgrading to the 1330, but like the smaller size of the 1210 (which was discontinued). It fits nicely in my motorcycle pack.

I think you will be quite happy with your system.

[wd6s]

Don't forget the difference between "logical" megabyte and base 10 byte count. A logical megabyte is 1024 X 1024 bytes, or 1,048,576 bytes, so a logical gigabyte is 1024 X (megabyte), which is 1, 073, 748, 124 bytes. In logical gigabyte there are nearly 74 MB more than in a base 10 count. Manufacturers/marketing uses what works best to sell the computer, and sometimes programmers confuse the issue in how a utility determines memory size - do they divide by 1000 or 1024? This does not resolve the issue of seeing less than the installed memory but is something to keep in mind as you work with the numbers.