Usable RAM stays at 2.75gb when upgrading from 3 to 4bg

[x100e_user]

Hi

I just upgraded my x100e from 3 to 4 gb RAM. While the change is recognized as installed RAM in the overview page, the usable RAM has not changed. It remained at 2.75gb. What am I doing wrong?

Btw, my maxium memory box is unchecked under msconfig boot. I was not ablw to find any memory remapping option in the BIOS.

1282mb are shown as reserved for hardware according to my resource monitor. I understand the graphics card takes some of that, but that much?

Grateful for any suggestions...

[x100e_user]

Hi

I just upgraded my x100e from 3 to 4 gb RAM. While the change is recognized as installed RAM in the overview page, the usable RAM has not changed. It remained at 2.75gb. What am I doing wrong?

Btw, my maxium memory box is unchecked under msconfig boot. I was not ablw to find any memory remapping option in the BIOS.

1282mb are shown as reserved for hardware according to my resource monitor. I understand the graphics card takes some of that, but that much?

Grateful for any suggestions...

[ColonelONeill]

Are you running 32-bit Windows?

[x100e_user]

Yes, I have 32-bit windows installed. Does this only allow for 3mb of RAM?

[x100e_user]

Hi, I found some answers on here:

http://forums.lenovo.com/t5/X-Series-ThinkPad-Laptops/X100e-memory-capacity-limits-with-32-bit-Win-7...

http://blogs.technet.com/b/markrussinovich/archive/2008/07/21/3092070.aspx

Most relevant response in one of the blog responses I found, albeit for XP and Vista, is below.

Still wonder if 2+1 is really giving me any edge over 2+2gb RAM or if I can just save the money and return the 2gb to the store.

Anna N
28 Jul 2008 5:19 AM
My rule of the thumb, 1GB for XP on subnotebook (more RAM means higher power and shorter battery life), 2GB for every other XP, 4GB for Vista. More than 4GB only on 64bit Vista AND only if you have profiled demanding application you need to use and it needs more RAM.

Yes, there's a reason to have 4GB under 32bit OS, and that is because most graphic cards have 512MB or less, so even after drivers' memory holes you have usually much more than 2GB available, and that's useful for caching (so for casual usage, too), especially under Vista. 4GB is (on current platforms) better than 3GB because of dual channel memory so 2x2GB means better memory performance than 2GB+1GB. This may change on triple-channel Nehalem, maybe 3x1GB will be better.

[ColonelONeill]

You'll need a 64-bit OS to get all 4GB. Going from 3 to 4 isn't too significant on the X100e as you'll likely be bottlenecked by the CPU. Still, if you need the RAM, by all means. Heavy browsing will require a fair bit of RAM.

[x100e_user]

Many thanks. I'm just curious why it is capped at 2.75 and not 3.5 or so...

Will a 64bit OS give me problems with the drivers and applictions on the x100e?

[The_Solutor Guru]

Don't forget the video memory, with 4GB installed and a 64bit OS you will see 3.75 GB or so...

[x100e_user]

thanks. Are you saying that my video memory is taking 1.25gb right now? If it just takes .25gb then i am wondering what happens to the remaining 1gb. can the applications or any part of the OS make good use of that? if not i'll just put back the 1gb card and return my second 2gb card to the store.

[The_Solutor Guru]

your video memory is using 256MB, the other GB is not accessible because the 32bit OS.

You can't access that GB with a 32 BIT OS.

BTW you it can be used with some (but not all) ramdisks.

They came very handy, if you are using a solid state disk, to put on them the temp folders  and  browsers' caches, limiting the SSD wearing.

But even with a standard HDD browsers' cache on ramndisk can speed up them.

Keep also in mind that, if you want, you can use (in a legit way) a 64 bit OS of the same level of the installed one.

[x100e_user]

many thanks, this is very helpful. i think i will return it, going back to 3gb. may be just too much hassle to install 64 bit OS now...