How is this possible ... 3 GB Dual Channel DDR2 SDRAM, in 2 slots ... how ..?

Question

i happened to come across the vostro line from dell
specifically, the vostro 1400 for example
http://configure.us.dell.com/dellstore/config.aspx?c=us&cs=04&kc=6W300&l=en&oc=bqdwj2j&s=bsd
i find the memory options listed as below,
3GB Shared Dual Channel DDR2 SDRAM at 667MHz, 2 DIMM
if someone could please help me understand how they make it possible

Answer 1

A very good question, one which I would like Dell to answer. According to the service manual on this model, it has two DIMM slots, and each slot accepts DIMMs with capacities of 512MB, 1GB, and 2GB. It also specifically says in the manual, the DIMMs must be matching sizes to run in dual channel. As anyone can see, the numbers simply don't add up. My guess is that Dell is simply labeling this 3GB configuration as dual channel when in fact it isn't, because it most likely consists of a 2GB stick and a 1GB stick.

Answer 2

No can do, my friend ... UNLESS... there is 1GB or 2GB of RAM onboard.

This is neither uncommon nor anything new (to have RAM integrated on the MB) where notebook PCs are concerned.



My conclusion (of course) is based on the posted specs of 3GB RAM being accurate. If so ONLY having onboard RAM (either 1GB or 2GB) would make a total of 3GB DDR2 on a two module slot notebook possible.



sincere regards,

Philip T

Answer 3

It can run 3GB dual channel if the mobo supports asynchronous dual channel configurations. This allows differnent size RAM chips to run un dual channel mode.



If the mobo does not suppor this feature, then it is a typo - or at least misleading.



Technically, it could be 2GB + 1GB of dual channel memory only operating in single channel mode.



My guess is the mobo supports asynchronous dual channel memory configurations.

Answer 4

I followed the link provided and found this...



2GB Shared Dual Channel DDR2 SDRAM at 667MHz, 2 DIMM



this was on the righthand side of the webpage. If it states 3GB somewhere else, perhaps it's a typo...

Answer 5

Maybe those people at Dell are nuts. The one who wrote it was probably GOOD at copy-paste, and his copy editor probably lost his contact lenses. 1.5Gb ddr2 would be rare and expensive. My search could only turn out this expensive ECC one:

http://www.itbox.com.au/catalogue/details.jsp?productID=73640



BUT then, who knows, Dell might have partnered w/ a memory vendor that has started churning out 1.5Gb ddr2 sticks mainly for OEMs that is why there are no retail info available as of the moment.

Answer 6

One 2 gig DDR2 module and one 1 gig DDR2 module. The dual channel is built into each module.



If you buy this system I would have it upgraded to 2ea 2 gig modules for 4 gig ram total, shouldn't cost to much more.

Answer 7

It's possible - 1 x 2GB stick and 1 x 1GB stick. I'd go with the 4GB option if you have the $ and reason to do so. 2GB should be enough and would have you in great place.

Answer 8

1 + 2 = 3 ....

Answer 9

a 2 GB and 1 GB in different channels

Answer 10

a 2 gb ram and a 1 gb ram are used.

Answer 11

2 gb in one slot and the other 1 gb in the other slot........its always better to have individual rams in both slots...even if one fails the other would work and keep the system active....

Answer 12

Quite conceivable they have included 1GB onboard on the motherboard.

Alteratively, you could always call dell and ask them !

Answer 13

its possible that they do indeed make 1.5gb dimm modules ...

http://www.avadirect.com/product_details_parts.asp?PRID=7479



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