t400 memory ...will 1333 work with 1066(the standard ddr3)>

[T400plus]

I am buying kingston 4 gb module.For some reson it is easier to get the 1333 and it is a little cheaper.Will it work with my old 2gb (which is 1066).I intend to replace 1 2gb -1066 chip with a 4gb chip.

--T41 ,2.0GHz,1.5GB,160GB,14",windows 7
--t400 wxga+,p8400,----windows xp...

[Jakoob]

I think, it will work without problem as the motherboard should lower the frequency from 1333 MHz to 1066 MHz. Don't forget to check the manufacturer, I have problem on my T500 with Corsair and have to replace it by Kingston. (2x 4 GB)

[jayton4]

The 1333 memory will work fine at 1066. If you are using Intel Graphics, then you will want both SODIMMs to be the same capacity. Mismatched capacity (4GB+2GB) will cause weird lines on the screen.

See the Type B section on this page:
http://support.lenovo.com/en_US/diagnos ... D=HT001223

[T400plus]

Thank you jayton4.So what should I do,disable intel graphics.I own this slab for 3 years Now,But only now I intend to start warming it.IT has a upgraded XP with a vista license.I am going to install windows 8 on it after others have burnt their eyes with that.

[jayton4]

If you have ATI dedicated graphics, then I suppose you could disable Intel Graphics.

What you should do is get two 4GB modules since they are so cheap.

[mikemex]

Short answer is yes, it should work.

Long answer is that the frequency is controlled by a program called SPD and while the vast majority of modules have SPD settings for various frequencies, I've come to some that don't have settings for frequencies other than specified. It's not common but it may happen that you pop it in and it doesn't work, even if the module works fine in another machine.

It's a matter of trying, success is 99% waranteed.