Thinkpads Forum

Yes - I know, the T60 cannot see 4GB of memory. With 4GB installed, only 3GB is visible regardless of operating system.

However... I spent a few hours benchmarking memory performance with various combinations of 1GB and 2GB memory modules, and with 32-bit Windows XP and 64-bit Vista. With matching memory modules, the T60 memory runs in dual-channel symmetric mode. With mismatching memory, it runs in either single-channel or dual-channel asymmetric, probably the latter. Dual-channel symmetric gives a slight performance increase over the other two modes.

I won't bore you with the tables of performance results, so here it is in a netshell:

1. Memory performance is essentially the same between 32-bit XP and 64-bit Vista

2. My benchmark results show that memory performs about 8% faster in symmetric mode (matching modules) than in asymmetric mode (mismatching modules).

3. For best performance, install two 2GB modules. This allows the 3GB of usable memory to run in symmetric mode.

4. The real-world performance boost of symmetric mode vs asymmetric mode is negligible for most users. It's probably not worth the extra money if you're upgrading memory, unless you happen to get a second 2GB module for free like I did.

yeah i did quite a bit of research on this subject long time ago. back then most people were wondering whether to get 2X1gb. The overall performance gain was just about between 0-8% but that mostly depends on the aplication.

To RonS,

Just curious, how do you get free RAMS?

I ordered one 2GB module, but there were two of them in the box. I'm contacting Crucial about it, but in the meantime I thought it would be good to do some benchmarking.

Very nice. How much are those now? I am thinking to upgrade, but just waiting a little while for the price drop.

It's about the same for the G.Skill DDR2-667 CL4. I buy them, just to seen how it goes... Useless for most people (except if you buy a barebone without memory, if you can sold your module at good price or if you can use them to upgrade an other laptop).

http://forum.thinkpads.com/viewtopic.php?t=46850



RonS did you noticed performances improve in common application between 2 x 1 GB and 2 x 2 GB ?

did anyone try if its possible to put 4gb of RAM into T60. Have windows use 3gb and somehow enable the other 1gb to use it for RAMDISK. That way you could put your swap file there.

mattbiernat wrote:did anyone try if its possible to put 4gb of RAM into T60. Have windows use 3gb and somehow enable the other 1gb to use it for RAMDISK. That way you could put your swap file there.

The T60 chipset will only recognize the first 3GB. I really like your idea, but I don't see how it could work.

RonS wrote:The T60 chipset will only recognize the first 3GB. I really like your idea, but I don't see how it could work.

is this because of the core duo processor or bios?   would installing a C2D processor with 64-bit windows help or would it still only see 3GB?

erik wrote:is this because of the core duo processor or bios? would installing a C2D processor with 64-bit windows help or would it still only see 3GB?

I believe the 3GB limitation is from Intel's chipset. I've installed a C2D in my new T60P, and installed 4GB of RAM. With Gentoo AMD64, only 3GB is recognized. I also dual boot to 32-bit Win. 2003 Enterprise Svr., which only sees 3GB.

ahh, ok.   that's disappointing but still good to know.   thank you.

caseyse wrote:I believe the 3GB limitation is from Intel's chipset. I've installed a C2D in my new T60P, and installed 4GB of RAM. With Gentoo AMD64, only 3GB is recognized. I also dual boot to 32-bit Win. 2003 Enterprise Svr., which only sees 3GB.

Do you happen to know if the limiitation is solely due to the chipset or does the OS impact this as well, i.e. WinXP 32 running on a 64-bit processor will still only see/use the 3GB?

John

johnvndnbrk wrote:Do you happen to know if the limiitation is solely due to the chipset or does the OS impact this as well, i.e. WinXP 32 running on a 64-bit processor will still only see/use the 3GB?

if neither 32-bit 2003 enterprise server nor 64-bit gentoo linux can see all 4GB then it's definitely a hardware limitation.

johnvndnbrk wrote:Do you happen to know if the limiitation is solely due to the chipset or does the OS impact this as well, i.e. WinXP 32 running on a 64-bit processor will still only see/use the 3GB?

The T60/p has a limit of 3GB usable RAM. 32-bit Windows (both XP and Vista) is also limited to 3.25GB or 3.5GB RAM, even running on a 64-bit CPU.

The T61 has a 4GB limit, so if you run 32-bit Windows on it, you'll get to use 3.25 or 3.5 GB of RAM, but you can use all 4GB on a T61 if you use a 64-bit OS.

Pascal_TTH wrote:


RonS did you noticed performances improve in common application between 2 x 1 GB and 2 x 2 GB ?

bump...

Pascal_TTH wrote:RonS did you noticed performances improve in common application between 2 x 1 GB and 2 x 2 GB ?

When I use XP (32), the extra 1GB doesn't seem to make too much of a difference.

But when I use Vista 64 (which is my primary OS), that extra 1GB makes a HUGE difference. It seems like Vista really needs at least 3GB to perform well.

ahh, this thread brings back memories.   it's the entire reason why i performed my OS/memory test stickied above.

Thank you

RonS wrote:

Pascal_TTH wrote:RonS did you noticed performances improve in common application between 2 x 1 GB and 2 x 2 GB ?

When I use XP (32), the extra 1GB doesn't seem to make too much of a difference.

But when I use Vista 64 (which is my primary OS), that extra 1GB makes a HUGE difference. It seems like Vista really needs at least 3GB to perform well.

Ok, so based on your tests, tell me - is there a still a significant advantage in going from 2 x 1GB installed to 1 x 1GB + 1 x 2GB (3GB total)?

Or, by losing the dual channel/symmetrical is there only a negligible gain with this?

Trying to determine if it's worth it to upgrade to 3GB or if I would really have to get 2 x 2GB modules to really see the gain even if I am only using 3GB of that.

I had the 2x2gb installed. It sometimes would cause random error messages of the nature that the memory was out of bounds and could not be read. No big deal, but then I decided to split the 2x2GB and the 2X1GB across two machines into the 1X2 and 1x1GB. Havent seen any error messages since, and really havent noticed a speed drop between 4GB and 3GB in xp pro.

ducky2802, thanks for that interesting report. It's very helpful for people contemplating upgrading to 4GB.

2GB+2GB = symmetric dual channel mode
2GB+1GB = asymmetric dual channel mode

IOW the laptop's RAM will still run in dual channel mode either way, except symmetric dual channel is just a pitiful 2-3% faster max.

If one's ThinkPad already has 1GB installed from the factory then installing a 2GB stick for 3GB total makes absolute sense. Just for grins, that's how I configured my own T60 with a T7200 Core 2 Duo CPU running WinXP Pro.

But if one has to pull the factory 1GB stick in order to install two sticks of 2GB RAM just to enable the much hyped symmetric dual mode, one better hope that those two stick of 2GB RAM only cost 2-3% more than the cost of just one 2GB stick, because in the end, with only 3.25 or so GB actually usable out of 4GB total and memory bandwidth improved by only 2-3% max, one's really not scoring much of a deal.

Good info - my T60p (8744J2U) has 2 x 1GB installed so I would be ditching 1 x 1GB for a 2GB module. So the cost of the lost here isn't quite as significant.

Anyone buying a 1GB module? Or maybe I should wait to check my performance!

so how many ram slots are in T60P, 2??
I have 2 gig of ram, so how do I find out if I have 2X1gb or 1x2gb??

whizkid wrote:
The T61 has a 4GB limit, so if you run 32-bit Windows on it, you'll get to use 3.25 or 3.5 GB of RAM, but you can use all 4GB on a T61 if you use a 64-bit OS.

Not exactly, we don't know the memory limitations on Santa Rosa just yet. Anyone have a couple 4gb sticks to try?

Yoguess wrote:so how many ram slots are in T60P, 2??
I have 2 gig of ram, so how do I find out if I have 2X1gb or 1x2gb??

What is the part # of your system? I think most of the 2GB use 2x1GB - but as I look at the old reference sheets, not all of them.

Let me know the part, I will confirm it for you.

8743CTO

thanks Jay

Yoguess wrote:so how many ram slots are in T60P, 2??
I have 2 gig of ram, so how do I find out if I have 2X1gb or 1x2gb??

Here (Right Click and then Save Target As). Unzip it then open cpuz, go to SPD and check Slot 1 and 2 if none of them are empty then you have 1+1GB otherwise 1x2GB memory stick.

Yoguess wrote:8743CTO

thanks Jay

I guess I won't look this up for you - since it's a CTO (Configure to Order) it will be configured as you specified!

If I open PC Doctor then Open 'System Reports' then 'System Information', mine shows 'Total Number of Memory Modules & Total Number of DIMM Slots" The Number of DIMM slots = 2, so just check the other to see if it's 1 or 2. If it's 1, you have one free!

Hi!
I've just downloaded the "Mobile Intel® 945 Express Chipset Family" Datasheet and Intel clearly states that it supports 4GB of RAM. Why t60 just sees 3GB.. there is somenthing weird.