1GB RAM showing as 512MB

I have recently bought a 1GB stick of RAM,  the problem is that it shows up as 512.  I have just flashed my BIOS with the most recent update.
The specs are as follows

    * 1GB (Size)
    * PC3200 - 400mhz (Speed)
    * CL 3 (Cas Latency)
    * 128x64 -Built with 128Mx4Bit Dram (Hi-Density Dram)
    * Un-buffered
    * Non-Registered
    * 184Pin
    * Non ECC

* I have a stick of 512mb with the same specs in already and just updating

Motherboard = Epox 8KDA3J and from what I can see this supports both double and single sided memory aswell as Hi-Density RAM.

Link to motheroard manual:


Any help would be appreciated.
Thanks in advance,
Who is Participating?
Gary CaseConnect With a Mentor RetiredCommented:
r.e. sparkmaker's question "... how in the hxx they support 3gb ..." ==>

The board does indeed support up to 3GB of memory.   You can mix/match any size modules, BUT they must be single-sided (single rank) modules.   You have simply bought a module with the wrong rank structure, so the system is only "seeing" 1/2 of it.   There's nothing wrong with the module you bought -- it's just not the right one for your board.

By the way, your board is NOT a dual-channel capable board, so you can ignore all the comments relating to that.

Is your 512mb module single-sided?   If so, you should be able to "see" all of your memory, even with a double-sided 1GB module, if you install them in one of the configurations shown on Page 3-6 of your manual.   But the best thing to do is use ALL single-sided modules.   Then you'll always "see" all of your memory.
Seeing only half the actual memory is a classic case of installing incompatible RAM on your motherboard.  If you want RAM that is guaranteed to work, try Crucial: http://www.crucial.com/store/listparts.asp?Mfr%2BProductline=EPoX%2B+Motherboards&mfr=EPoX&tabid=AM&model=EP-8KDA3J&submit=Go
VMSZealotConnect With a Mentor Commented:
The other thing to check is that your motherboard supports the amount of memory that you're trying to install.  If, for example, your motherboard has two slots (which can take 1GB DIMMs) but it can only support 1.5GB, then regardless of how you slice it the last 512MB will be ignored.

I agree with Callandor though, it's more likely to be dodgy RAM - and I can't think of a better vendor than Crucial.
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TDC_LuCiFeRAuthor Commented:
Thanks for the input guys,  the board supports 3GB of RAM though,  I have contacted the vendor and im waiting on a reply.

Will check back later
Is the MB trying to run in dual channel mode? Does the MB allow you to have different size sticks of ram?
TDC_LuCiFeRAuthor Commented:
I have checked through the specs thoroughly and I dont see anything about Dual Channel mode for this board,  is this necessary to make the 1G work fully?

I have just got the 1G stick in at the moment but have added a 512 stick of the same specs and it works fine alongside but only making up 1G and not 1.5G.  And in the manual also it is allowed to use various sizes of sticks.
CallandorConnect With a Mentor Commented:
Dual channel has nothing to do with seeing half the RAM you're supposed to.  When enabled, it doubles the memory transfer rate, not the capacity.
Dual channel is not necessary to make the one gig of ram work to its full capacity.  Are all the timing and latency settings correct for your RAM in the BIOS?  Be sure they are all at factory recommendation and not overclocked or anything.

If thats not the case I'd have to agree with Callandor and say its just incompatible.  It could be because the chip density is too high.

Also here is a link to the Corsair memory configurator: http://www.corsairmemory.com/corsair/configurator_search.html

Crucial is a good brand as well, its all personal preference

Good luck, keep us updated!

TDC_LuCiFeRAuthor Commented:
Yup i went through all the settings in the BIOS and set it to Best performance,  I am thinkin myself that the RAM is just not compatible and im waiting to hear from the supplier.
Thanks for the help guys and ill check back soon and split the points or something if i dont get the solution.
MarkConnect With a Mentor Commented:
The Epox page for this MB says -->http://www.epox.com.tw/eng/products_content.php?ps=361
System Memory:
3 DDR SDRAM DIMM sockets Support 400 DIMMs architecture in 128/256/512Mb technologies up to 3 GB system memory.

Can anyone tell me how in the hell they support 3gb out of 3 slots that only support" 512mb technologies" at the most.

Your board can only handle 512mb ram modules.
Kingston has this to say about there modules in this board
-->Virtually any configuration up to 1.25GB can be reached using any combination of Kingston's 128, 256, 512MB, and 1GB modules.

Thats quite a bit short of 3gb, but they also sell the 1gb module
Gary CaseRetiredCommented:
... by the way, the board will support a single double-sided module in any slot.   If you remove your 512mb module, and plug in just the 1GB module, you should see 1GB.
stevepoConnect With a Mentor Commented:
I agree it seems very odd that several major memory manufacturers (not including Kingston) and Epox themselves say that the board supports 3 GB and the memory manufacturers are all selling a 1 GB module for this board yet Epox says it only supports "512 mb technologies" and there are only 3 RAM banks on the motherboard.

Kingston could very well be correct, yet the majority of documentation/resources is saying this board supports 3 GB so it still seems as if the new 1 GB memory module being installed here is no good.

Hope all goes well in your talks w/the supplier and you can get an answer or a refund if need be.

I don't see anywhere unless I missed it where you say who the manf. of the memory is or from who it was purchased. I would first talk to the supplier you got it from. I would not rule out mis-labled memory or the possibility that it is defective. Call your supplier or the manf and talk to them and tell them the issue you are having. If they are reputable they should be more than happy to assist you as long as it is not outside the warranty period and even then a reputable one should be more than happy to provide assistance with tips or troubleshooting.

Actually I misrepresented the 512Mb technologies.I didn't interpret  the small "b"correctly. If stated correctly it is meant to be read as 512 Megbit -(Not Mega Byte)technologies which refers to high density ram modules. The memory bank schema that Gary refers to is the key to the answer as it talks of using SS(single sided) and DS (double sided )modules in  certain slot configurations.
Got us both with the 512 Mb! I should've picked up on that :o)
TDC_LuCiFeRAuthor Commented:
OK guys great feedback,  ill try the 1G module in some of the other slots and keep the 512 out for the time being.  I will try this tomorrow evening after work and get straight back to the forum,  i have a few points extra too so if i can get this sorted ill reward all of u well.
TDC_LuCiFeRAuthor Commented:
OK i removed the 512 module and from what i can see the memory is double sided,  there is some kind of heat shield over the module.

I tried it in slot 1 alone and it still comes up as 512mb.  From what i can figure out the board should support 1GB in any slot without the 512 module in right?

Still comes up as only 512mb being seen.
TDC_LuCiFeRAuthor Commented:
The supplier has said it is not compatible with my board and cant seem to explain why totally but has offered me a refund or the correct RAM so ill split the points.
Cheers guys
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