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BigMark · Jan 3, 2002, 10:26 PM

ADC web page says :

"Total RAM capacity using the highest-density devices available is 384�MB and is limited by the space available for the SO-DIMMs. The bottom slot can accommodate a 1.5-inch SO-DIMM with up to 128�MB of SDRAM. The top slot can accommodate a 2.0-inch SO-DIMM with up to 256�MB of SDRAM...."

HOWEVER, Guru 2.9 tells me that the max. RAM is 1024MB.

Which is true? Is there now a 1.5 inch 512MB RAM chip available?

seanyepez · Jan 4, 2002, 01:48 AM

Yes. There are 512-megabyte memory modules out for notebooks. The top slot can accomodate standard 512-megabyte modules, but the bottom slot must have low-profile RAM. These modules are generally more expensive than the standard modules.

Graymalkin · Jan 4, 2002, 04:07 AM

Officially the Lombard only supports 384MB of RAM because any more than that and you may or may not be able to do sleep swapping. The PBs have the rather cool ability to retain data in RAM in sleep mode if you pull the battery out and swap in another fresh one. However with DIMM sizes exceding 256MB the internal battery just can't supply enough juice. Unofficially a 512MB module works just fine as long as you don't plan to swap the battery out in sleep mode. The top SODIMM slot can use a regular size SODIMM module but the bottom module needs a low prodile one. If you can find a low profile 512MB module you're going to pay top dollar for it.

BigMark · Jan 4, 2002, 06:21 AM

Originally posted by Graymalkin:
<STRONG>Officially the Lombard only supports 384MB of RAM because any more than that and you may or may not be able to do sleep swapping. The PBs have the rather cool ability to retain data in RAM in sleep mode if you pull the battery out and swap in another fresh one. However with DIMM sizes exceding 256MB the internal battery just can't supply enough juice. Unofficially a 512MB module works just fine as long as you don't plan to swap the battery out in sleep mode. The top SODIMM slot can use a regular size SODIMM module but the bottom module needs a low prodile one. If you can find a low profile 512MB module you're going to pay top dollar for it.</STRONG>

Many thanks for a succinct answer. MacNN needs a few more to-the-point posters like yourself.

seanyepez · Jan 4, 2002, 08:23 AM

I used to sleep-swap my batteries in my Lombard with 512 megabytes of RAM. What gives?

siegzdad · Jan 4, 2002, 08:28 AM

Don't forget that when the Lombard was released, large capacity SODIMMs were not available. The limit may have been because of what capacity RAM was available at the time.

spiky_dog · Jan 4, 2002, 12:48 PM

Lombards can only take low-density chips. This is what limits it to 384 MB, as a low-density 256 MB DIMM is twice as large as a normal one (thus you can't fit two in). I found this out after my Lombard only recognized a high-density 256 MB chip as a 128 MB. For the poster who claims to have had 512 in his: are you sure your laptop is a Lombard, not a Pismo?

vmarks · Jan 4, 2002, 08:06 PM

Originally posted by spiky_dog:
<STRONG>Lombards can only take low-density chips. This is what limits it to 384 MB, as a low-density 256 MB DIMM is twice as large as a normal one (thus you can't fit two in). I found this out after my Lombard only recognized a high-density 256 MB chip as a 128 MB. For the poster who claims to have had 512 in his: are you sure your laptop is a Lombard, not a Pismo?</STRONG>

Hey, check out my modules here:

This is a low - profile module that gets the iMac revision A up to 512mb when two are used. No reason on earth why you couldn't make a lombard have 512mb ram total. This module was originally intended for IBM Thinkpad T20 and T21 (2647) series. It works great in 1998 and 1999 year macintosh using SO-DIMM. I'm betting if I can find (afford) a 512mb module intended for the same IBM Thinkpad, it should work. Even if 1gb doesn't, 512 will for certain.

Surfer · Jan 6, 2002, 12:13 PM

Yes, the lombard can physically accept up to 1GB of RAM, but there are a few differences between the Pismo and Lombard ram modules!

The lombard memory chip manager can only address RAM modules with 128 bit chips, see here http://developer.apple.com/qa/qa2001/qa1040.html

This means that you can use the same chips as the PISMO and Ti machines if the modules have the required setup seen in the link above. If the modules are used with 256 bit chips the lombard machine will only recognize half the amount of RAM.

I purchased one lower slot 256 module and one 256 top slot module and everything works great!!!

Hope that helps!

slugslugslug · Jan 25, 2002, 07:01 AM

okay, it seems that 1 GB of RAM is theoretically possible, but does anyone actually sell 512-MB DIMMs that'll work in it?

All the vendors (transintl, OWC, memorytogo, boundless tech) I've looked at who list their memory upgrades according to compatible machine sell only 256-MB DIMMs (high- and low-profile) that they say work in a Lombard. It appears to me that it's not a matter of the configuration of chips on the DIMM that's off, but the fact that all the 512-MB DIMMs I've seen listed are PC100 or PC133 boards, and the Lombard uses PC66 DIMMs.
www.transintl.com has an article on their site touting the fact that you can now get 512 total on a Lombard.

So, yeah: does anyone know any places that sell PC66 SO-DIMMs that use 128 megabit devices for a total of 512 megabytes? Or know of places with salespeople knowledgeable enough to work this out with me on the phone?

thanks..

tooki · Jan 26, 2002, 12:56 PM

SDRAM is downwards compatible: PC133 will work in PC133, PC100, or PC66 systems; PC100 will work in PC100 and PC66 systems.

But remember the chip density: it relates DIRECTLY to the physical dimensions of the card. Using 128Mb chips, a 512MB module will be a full-height (2") card -- too big for the bottom slot.

Since no one seems to know for sure, here's my educated guess: assuming that the Lombard's memory controller supports this much, the maximum is probably 768MB, as a full-height 512MB on the top and a low-profile (1.25") 256MB module in the bottom slot.

Be sure to buy your RAM from someone with a liberal return policy!

tooki

seanyepez · Jan 26, 2002, 04:55 PM

Crucial.com, despite having the highest-quality RAM on the market, has a terrible restocking fee on purchases that don't fit. I believe it's soimething like 15%.

vmarks · Jan 26, 2002, 07:07 PM

I have 512mb installed in my Lombard using two 25mb modules like the one pictured above.

It's the one used in the Thinkpad t21 and t22 (2647 series) and can be purchased from Crucial with no worried- it just simply works, because the T series thinkpads have the same requirements as the lombard for memory controller chip.

Victor Marks
[email protected]