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RAM upgrade - one slot or two?

alanhll asked
Medium Priority
Last Modified: 2010-04-25
(Nice to be back after a while - no computer probs!).

I've got a HP Vectra VL400 PC. I have 256 MB RAM spread over the two slots. According to HP it will take 512 MB max. Could this all go in one slot, or would I have to get 2 x 256 MB?

Also, briefly, what's the deal with 'double-sided'. Is it better/worse/preferred/no different?


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hmmm, Crucial shows 3 slots.... for a VL 400mhz... is yours a different model?


but.... I do believe that the VL400 only had two slots...

DOUBLESIDED... just refers to the components on the memory module... being on both sides of the substrate... not good or bad.. its just the way they build them. But some systems cannot recognize the components on both sides... it may see them as one bank (components on one side), two bank (components on both sides)... if you had two modules installed, and one was a doublesided, and one was single sided, the system might see two banks, or three if it was capable of recognizing both sides of the doublesided module

because the system is limited to 512mb... I would think that you will be better off getting two modules (256mb).. single sided... I have a feeling that it may not recognize the second bank on a doublesided module



I beleive that Oldgreyguy is correct.

I don't think that you can have double sided and have it work correctly.  So single sided RAM is what you will need.

There is confusion concerning single side vs. double side memory. This is not the important factor. It is wether the module is single bank or dual bank memory. Single side does not necessarily mean single bank and the same for double side...does not necessarily mean dual bank. You must check the stucture of your mainboard's memory system against the specifications of the memory module. As again, the number of slots does not indicate the number of banks available on the motherboard. Example, two slots may provide two banks...could use 2 single bank modules or only 1 dual bank module or two slots may provide four banks in which case any modules, single or dual bank would work.
So find out how many slots provide how many banks on your mainboard and then populate them with the appropriate memory( single bank or dual bank ). Combinations can be used but is more complicated to determine correct bank assignments for population.


The current 128 MB RAM modules are double sided.

The computeris a PIII 800 mhz.




I still don't know what to get.

Awaiting a clear answer,



Can I get away with just 1 x 512MB (which would be cheaper than two modules)?
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