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hawihoney

What type of RAM do I need?

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Hi,

 

I'm no hardware guy so please excuse my question. I own a Lime-Tech MD1500 with the ASUS P5B-VM DO board. I would like to put the RAM on this board to the max. What type of RAM do I need to buy and what size is possible?

 

Many thanks in advance.

 

Regards

Harald

 

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Why would you want that? unRAID will probably not support the max. RAM your board supports.

 

 

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The board supports Dual-channel DDR2 800/667/533.

I would get as high quality with the highest speed possible.

If you can afford, go to 4GB.

If you have extra money and plan to install allot of packages or do allot of work on your server you can max it out to 8GB.

I believe Tom said he was going to enable PAE which would allow you to use the MAX ram of 8GB.

 

I'm using 8GB in my machine, however I recompiled the kernal and enabled PAE.

I install allot of packages too, PHP, Perl, Python, Lighttpd. and rTorrent.

 

4GB should yield you enough to do most anything.

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Why would you want that? unRAID will probably not support the max. RAM your board supports.

 

I want to install this monkey UPnP server. Last time I did it I ran out of memory.

 

Regards

harald

 

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The board supports Dual-channel DDR2 800/667/533.

I would get as high quality with the highest speed possible.

If you can afford, go to 4GB.

 

Thanks for this information. So for 4GB I would buy 4* Dual-channel DDR2 800 1GB, right?

 

Thanks a lot.

Harald

 

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Why would you want that? unRAID will probably not support the max. RAM your board supports.

 

I want to install this monkey UPnP server. Last time I did it I ran out of memory.

 

Regards

harald

 

In its normal configuration unRAID has no "swap" space defined, so all concurrent running process must fit into memory and share that same memory with the disk buffers. 

 

When you ran out of memory, was it because there was not enough RAM to load the UPnP server into memory, or was it that the server ran out of memory eventually after it allocated memory it did not free? (possible memory leak)

 

 

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Thanks for this information. So for 4GB I would buy 4* Dual-channel DDR2 800 1GB, right?

I would purchase Dual Channel DDR2 800 2x2GB. They come in kits. from $60 to $99/w Rebate.

This leaves the other slots open for more memory later on.

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When you ran out of memory, was it because there was not enough RAM to load the UPnP server into memory, or was it that the server ran out of memory eventually after it allocated memory it did not free? (possible memory leak)

 

The UPnP server started just fine. After I declared all media folders the server started to eat up all memory. So I stopped that experiment and waited for more memory to be supported.

 

Thanks

Harald

 

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I would purchase Dual Channel DDR2 800 2x2GB. They come in kits. from $60 to $99/w Rebate.

This leaves the other slots open for more memory later on.

 

Good idea. There are only 2 compatible 2GB modules in the Asus list of this board (Kingston KHX6400D2K2/2G and ELPIDA EBE21EE8ABFA-8E-E). Don't know what these SS/DS or Channel A/B/C means but I will try to get two of these.

 

Thanks

Harald

 

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My experience is that you need to look carefully at the voltage requirements of the memory and the voltage capability of your MB.  If the MB has no RAM voltage adjustment, you need to get memory that works at 1.8V.  If your MB supports increasing the voltage, you can get slightly faster RAM that needs 1.9V, 2.0V or higher.

 

I have had good luck with Gskill memory.  I sent them an email asking if they were compatible with my MB (they were not listed as compatible), and they said they guaranteed it would be.  I now have 3 Core2 computers each running GSkill memory.  One is using standard 2x1G 1.8V, one is using 4x1G 2.0v, and one is using 2x2G 1.9v.

 

I have heard that some MBs are more finicky about RAM than others, but have never had a problem personally with RAM incompatibility.  I will sometimes read the Newegg forums about the MB, and find people that post the memory they are using.  If I see 2 or 3 having a good experience with a particular brand / model that is at a good price, I will usually go with that one. That's how I first learned about Gskill.

 

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A lot of the RAM/Voltage/MB problems were resolved when the Enhanced Performance Profile portions of the SPD standard were added.... before, the SPD was often populated with the advanced performance mode, which required more than 1.8V, only... and the motherboard would obligingly read the SPD and set the timing as such, but if your MB was set on AUTO for it's ram voltage, the RAM only got 1.8V and failed... catch 22 on setting up the motherboard... NOW, the Jedec (first read) portion of the SPD gets set with some rather slow timings (stock?) so that the RAM will work at 1.8V, and the EPP profile in the SPD has the advanced timimgs which require more volts...

 

;)

 

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A lot of the RAM/Voltage/MB problems were resolved when the Enhanced Performance Profile portions of the SPD standard were added.... before, the SPD was often populated with the advanced performance mode, which required more than 1.8V, only... and the motherboard would obligingly read the SPD and set the timing as such, but if your MB was set on AUTO for it's ram voltage, the RAM only got 1.8V and failed... catch 22 on setting up the motherboard... NOW, the Jedec (first read) portion of the SPD gets set with some rather slow timings (stock?) so that the RAM will work at 1.8V, and the EPP profile in the SPD has the advanced timimgs which require more volts...

 

;)

 

 

Thanks for your answer. I didn't understand one single word of your text. As I wrote in my initial message - I'm no hardware guy. I'm just looking for someone who owns that motherboard (someone should have it - it's the Limetech board) and successfully increased RAM.

 

Harald

 

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Thanks for your answer. I didn't understand one single word of your text. As I wrote in my initial message - I'm no hardware guy.

 

Translation:

 

In BIOS there are two ways to specify your memory timings - manually or automatically.  The automatic setting is the default.  It is sometimes called SPD (who cares what that means, it is just the auto setting).

 

The way the auto setting works is the BIOS asks the memory "How fast are you" and the memory says "I am this fast".  Based on that, the BIOS sets the timings to the memory.

 

Now some memory (high performance memory) is able to run very fast BUT ONLY if it gets more juice (volts).  So if the BIOS asks this memory "How fast are you" and that memory says "I'm screaming fast", then the BIOS will dutifully set the timings to screaming fast.  But guess what, it won't work UNLESS the BIOS also increases the volts to the memory.  Most MBs don't do this automatically (many MBs don't even have the ability to adjust memory voltage).  So people put this fast expensive memory in their computers, turn it on, and start getting errors.  This causes lots of support calls, returned memory, returned MBs ... basically no one is happy.  People say "this memory is not compatible with my motherboard" and buy the slow "value" RAM - and it works no problem.

 

So as jimwhite explains it (and I didn't know this before), when newer memory (that follows the updated standard) is asked "How fast are you", it responds with "I'm kinda slow if you only give me 1.8v (the standard memory voltage)".  BIOS sets kinda slow timings.  Memory works.  Most people don't know or care that they're losing performance due to slow memory timings.  But people that DO know and care will go into the BIOS, set the timings manually, AND boost the voltage.

 

I'm just looking for someone who owns that motherboard (someone should have it - it's the Limetech board) and successfully increased RAM.

 

I think people have answered.  But the truth is, if you buy memory that meets the published standard from you MB, I doubt you'll have problems.  IMO, the issue explained above is mostly the reasons for all the fuss about memory and motherboards.

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There are only 2 compatible 2GB modules in the Asus list of this board...

 

I don't think they keep these lists anywhere near up to date, so there should be tons of options for you to choose from.  I often use RAM from Crucuial, and I have never had any incompatibility issues with any brand of RAM I've purchased.  You could try this link http://www.crucial.com/store/listparts.aspx?model=P5B-VM.  Like the others said, I would go for a 4GB kit (2x2GB) of DDR2-800.  Note that DDR2-800 is also called PC2-6400.  It looks like Crucial gurantees compatibility (though I've never looked into the guarantee).  Disregard the recommendations at the top (because they are for slower RAM...I don't know why) and scroll down to find the other options.  They also say that there are some faster RAM types that are compatible, but I would probably shy away from those since those speeds are not mentioned on Asus's site.

 

When I'm looking for RAM and am not in a terrible rush, I typically watch BensBargains.net and TechBargains.com for deals.  When I find one, I try to read the comments to see whether people have had good experience with the particular make/model.

 

 

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