4GB Memory Vista 32b T61

[T23_Owner]

I have been reading all about having 4gb memory with Vista Ultimate 32bit but I can't seem to answer this question of addressable space.


Here is my dilemma.

If you have 4gb memory in a T61 with windows Vista Ultimate 32b it will show 3gb per the sticky above. Now. There are lots of things that use memory like the video card, drivers etc. So, my question is this. If I install 3gb memory the video card will use some of that memory but if I install 4gb memory and vista only reads 3gb will my video card and other hardware utilize the missing 1gb of memory?

Will I benefit at ALL from installing 4gb of memory? I figure that the system uses memory interleaving and having 2 2gb dimms in there will at least spead up the intel integrated graphics.

What thinks???

[erik]

the amount you can use in windows depends entirely on the BIOS and hardware mappings.   if you install 4GB physical in a system with integrated video then a 32-bit OS might see up to 3.5GB addressable.   most see 3.25GB, 3.125GB, or 3GB addressable.

if you install 4GB physical and only see 3GB addressable then you're no better off than by installing 3GB physical.   this is because the address spaces for that last 1GB get mapped out for use by the hardware and cannot be used by the OS.   if an address space is mapped out then nothing else can occupy it, including physical memory.

since i don't have a T61 with integrated graphics available i can't say exactly how much you'll get in the end.   my gut feeling is that you'll only see 3GB.   i couldn't see more than 3GB in my T61p and that leads me to believe that lenovo's BIOS has mapped out the 3~4GB space entirely.

if you feel like experimenting after reading the above then that's up to you -- just don't get your hopes up.   if the results are higher than 3GB addressable then i'll add the results to the sticky.

[T23_Owner]

But the question is... if the memory for hardware gets mapped out to the unseen 1gb. That would effectively give you more memory since it does not need to be mapped out the the 3gb. So lets say the video uses 256mb.

If you install 3gb of memory you will see 3gb but have only 2.75 available.

If you install 4gb you will see in windows 3gb but still have 3gb available because the 256mb gets mapped out to the unseen 1gb.

This is what I am wondering.

[erik]

integrated video is typically mapped in the 3~4GB range so there's a 99.9% likelyhood that 4GB physical and 3GB physical will both show 3GB available to a 32-bit OS on a T61/p.   i highly doubt you'd see anything less than 3GB.   afaik, no one has ever reported this issue in the forum and there are a good number of users with 3GB physical memory in T61/p thinkpads.

if your T61 came with 1GB physical and you're looking to add more while sticking with a 32-bit OS then my recommendation is to install one more 2GB module for 3GB total.   the extra $90+ you would spend on a second 2GB module could be put to better use in my opinion.   even if you could get 3.125GB or 3.25GB addressable, you'd be spending $90+ for that extra 128~256MB.   that's a lot to spend for such a small gain.

[ran007]

the amount you can use in windows depends entirely on the BIOS and hardware mappings.   if you install 4GB physical in a system with integrated video then a 32-bit OS might see up to 3.5GB addressable.   most see 3.25GB, 3.125GB, or 3GB addressable.

if you install 4GB physical and only see 3GB addressable then you're no better off than by installing 3GB physical.   this is because the address spaces for that last 1GB get mapped out for use by the hardware and cannot be used by the OS.   if an address space is mapped out then nothing else can occupy it, including physical memory.

since i don't have a T61 with integrated graphics available i can't say exactly how much you'll get in the end.   my gut feeling is that you'll only see 3GB.   i couldn't see more than 3GB in my T61p and that leads me to believe that lenovo's BIOS has mapped out the 3~4GB space entirely.

if you feel like experimenting after reading the above then that's up to you -- just don't get your hopes up.   if the results are higher than 3GB addressable then i'll add the results to the sticky.

I may need to disagree. The day I received my T61 with 4GB and the 170M video, I booted it up, and XP Pro only saw 3GB in Task Manager. So I installed Windows 2003 Server (which we all know is XP with a chastity belt on). Off the bat it shows 4GB in Task Manager. I know its the BIOS (of course) and the OS.

[erik]

I may need to disagree. The day I received my T61 with 4GB and the 170M video, I booted it up, and XP Pro only saw 3GB in Task Manager. So I installed Windows 2003 Server (which we all know is XP with a chastity belt on). Off the bat it shows 4GB in Task Manager. I know its the BIOS (of course) and the OS.

disagree with what?   we already know that XP 32 only sees 3GB and server 2003 can see all 4GB.   in fact, the results are stickied to the top of this forum.

http://forum.thinkpads.com/viewtopic.php?t=49703

since you have a 170M your results don't help T23_Owner since the question here is with integrated graphics, not discreet.