# Memory Questions?



## unpopular (Jan 23, 2016)

I have a few questions about memory upgrades. I currently have 16gb, but for what I've been doing lately that just isn't nearly enough. Ideally I'd have 64GB+, but I cannot afford that - unless I find some deal on ebay. So I am aiming for 24-56gb.

My question here is this. My Dell Precision system takes DDR3 1866 ECC registered ram. Will any ram that meets this specification work, or should I get the "system specific" ram at a premium?

Also, I sometimes see RAM for pretty cheap on ebay. I am assuming that it's being pulled from servers, but I've also heard of "counterfeit" memory on ebay being listed at one size but you end up with something significantly smaller, though I've only heard about this with memory cards.

Last, my system has two Xeon processors installed. I currently have two 4gb modules installed on each processor. When I upgraded to 16gb I bought one 8gb module. Does anyone know if this might result in any stability or performance issues; when upgrading should memory configurations ideally be matched on both processors, or is it OK to "mix and match"?

Thoughts?


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## bratkinson (Jan 23, 2016)

I have to wonder why you are using a multi-processor (physically separate processor chips) server oriented motherboard for 'normal' photo processing?  I have no idea whether products such as Photoshop and other modern editors can take advantage of physically separate processors vs a quad- or octo-processor all on one chip.  I know from my own observation that Lightroom doesn't fully utilize all 8 processors in the FX-8370 on my computer, but it does keep all of them at varying levels of 'busy' while exporting a group of photographs.

That said, on to your question -
I'm no 'RAM guru' but I do know that mixing RAM sizes and even manufacturers on the motherboard will cause the internal RAM-controller chipset to do 'extra work' to keep everything straight.   The problem is that each manufacturer and speed-rating of RAM is different from all others in terms of 'cycle time', usually described as 3 or 4 speeds expressed in nano-seconds (millionths of a second, commonly referred to as CAS#, RAS# to CAS#, RAS# precharge, and others).  The time needed for a particular stick of RAM for storing data, fetching data, as well as processor-to-motherboard-chip-to-RAM chip is critical in accessing data.  It's possible to modify onboard mobo bus speeds as well to improve overall performance.  I've never really 'dug deep' on the subject other than some minor tweaks ('guesstimates') needed for overclocking on my computer.

In my opinion, having memory of different speeds on the motherboard is asking for slower-than-expected response times.  Putting different speed RAM or even different sized RAM in 'paired' slots may result in anything from failure to boot to BSOD (Blue Screen Of Death).  On (I think) all the ASUS motherboards I've used to build and upgrade computers with through the years, if there's 4 slots for RAM, they are always 'paired' A-B-A-B where if two sticks are used, they should be in both A slots, etc.  That's due to the 'memory interleaving' capabilities where the mobo uses the paired slots as a 'micro' RAID where the first byte (or ?) of data is on stick #1, the next on stick #2, then back to #1, etc.  That allows faster storing and access to data as while one stick is 'storing', the other stick is 'precharging', all in 3-4 nanoseconds, of course.  In essence, data throughput is close to doubled.  Of course, per the ASUS instructions, memory interleaving only occurs if identical sticks of memory are in each of the A-A slots, or B-B slots.  Otherwise, issues of timing and size differences cause more 'overhead' time than would be saved.  Although it's possible on my present motherboard to individually define each of its 4 RAM slots with separate speed and voltage values in the BIOS screens, but that's far beyond my capabilities.

So, would installing additional memory be an improvement?  In my own experience, Lightroom and Photoshop Elements each can hold about 20-30 images in the 16GB of RAM in my computer before they have to start using 'work space' on my SSD to swap-out 'old' images to make room for new ones being edited.  I believe they both do their own 'paging' rather than allowing Windows to make paging decisions for them.  While bumping up my RAM to 32GB would allow more images in RAM before doing swap outs, I would still run into the same 'wall', just later than before.  (Note that I usually do editing in groups of 100-150 images, ie, 2-3 hour 'chunks' of work).  Instead, I chose to put Windows and all heavily-used software on SSD, as well as defining LR and PSE work spaces on the SSD as well for speed.  That way, my 'swap out/in' times have the least impact in my photo editing speed.

If you do add more memory, keeping the same speed as you currently have (1866) is recommended as it's possible that faster (and more $$$) RAM would 'go to waste' and be slowed down to run at 1866 speeds.

One other issue is that of the capabilities of the motherboard.  More recent motherboards can handle 32GB and larger, but boards older than, say, 2-3 years may top out at 24 or 16GB.  You'll have to read the motherboard instructions to find out what it's limits are.  It may be necessary to update BIOS as well to support larger RAM capacities and/or faster speeds. 

In short, put in some 'due diligence' on what would give you the best 'bang for your buck' in terms of speeding up your computer.  It might be slow processor speeds.  Even a quad-processor computer running at 3.0 ghz is noticeably slower overall than a quad processor at 4.2ghz.  It could be slow RAM.  Although the documentation for each processor indicates what it's 'normal' RAM speed should be, I know they can handle faster speeds, and perhaps slower than stated as well.  So double-check what RAM speeds are needed by your XEON processors. 

It could also be slow hard drive speeds.  That could be the result of using IDE drives or SATA 2 drives instead of SATA 3 drives. (Don't even THINK of using external USB or eSATA drives if you want any kind of speed at all!) Of course, your motherboard has to support SATA 3 as well, otherwise, your SATA 3 drives will run at SATA 2 speeds.  I've had good luck with Western Digital drives, and I know they come in three different access-time speeds.  Putting your system on WD 'green' drives will slow everything down, as that's their slowest (and quietest, and least costly) line of drives.  Their 'blue' drives are faster, and 'black' drives faster still...and more costly.  Of course, SATA 3 SSD drives beat hard drives by a factor of about 10...and have no moving parts, just a bunch of RAM that has the 'look and feel' of a very fast hard drive from the viewpoint of Windows and your programs as well as the MOBO.  For what it's worth, all my 'in process' pictures and work areas are on SSD.  Once done, they get moved off to my slow WD Green hard drives for long-term storage (and multiply backed up).  Also, for what it's worth, I have a cheap, 2MB, non-fan-cooled video card in my computer.  The difference of maybe 1/4 second to bring up a Photoshop image vs a pricey gaming-computer video card simply has no 'pay back' whatsoever for my usage.

In short, figure out what you need rather than 'blindly' upgrading.  The same applies to adding/upgrading camera gear, too!

Edit: as far as buying on ebay, I've learned the hard way to stay away.  I've knowingly bought used RAM, CPUs and motherboards when doing mass-upgrades for a client 10 years ago, and got burned about 1/4 the time.  For my own computers, I've stayed with new gear only, from reputable vendors.  And, for what it's worth, most of my last 3 upgrades were bought at Amazon.


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## unpopular (Jan 24, 2016)

bratkinson said:


> I have to wonder why you are using a multi-processor (physically separate processor chips) server oriented motherboard



The motherboard it s a T5610 Precision Workstation. It is not a server.



> for 'normal' photo processing?



Sorry, I know I posted this in the Digital Photography forum, but photography is only one use I have actually.

I am an animation and visual effects student, so Photoshop is only one program I use. When I am not editing photos though, I am frequently working on extremely large 16 or 32 bit height map files in the 200MP range. Fortunately, they're greyscale, so Photoshop isn't necessarily the problem.

I'm currently studying Cinema 4D, Houdini, Maya, After Effects and Nuke. Frequently I'll flat out run out of memory. I'll admit, a lot of that specifically is inexperience and poor optimization or just making stupid mistakes with order of magnitude. But really 16gb is WAY too little headroom - especially when I forget that 1000^3 is a heck of a lot bigger than 100^3 

Also I frequently have to have more than one of these programs open with large files loaded. For example, I might have Photoshop open to edit a texture or some graphic element, while having After Effects or Cinema 4d opn. Or I might have Cinema open and caching an Alembic file to use in Maya. Or I might have Houdini open and doing something idiotic no amount of RAM handle .. because it's REALLY easy to do that in Houdini.



> I have no idea whether products such as Photoshop and other modern editors can take advantage of physically separate processors vs a quad- or octo-processor all on one chip.



As I understand it, the operating system and associated libraries (openMP, openCL) handle thread scheduling, not software. So basically what it does is say "I have this list of stuff I need done all at once" and the OS is responsible for dividing those tasks according to available resources.

If every application were responsible for scheduling and load balancing it would be a free for all.

The software I use do utilize all available cores for most situations, and in the case of 3d rendering and simulations they are highly optimized for multithreading. But one significant advantage of having 24 threads available is that I can set thread utilization for larger processes that might take hours to, say 20 or 22 and still have a very usable machine for doing other assignments, catching up on tutorials or watching cat videos.

If I had 8 threads are available a greater percentage of the the processor capacity is taken up. If I freed two threads on an 8 thread machine, I would have used up 1/4 of the resources available, which is way more than is necessary for cats on youtube.

I did look into the many core i7 options, but none were cost effective, especially when considering that the machine I got was refurbished.



> I'm no 'RAM guru' but I do know that mixing RAM sizes and even manufacturers on the motherboard will cause the internal RAM-controller chipset to do 'extra work' to keep everything straight.   The problem is that each manufacturer and speed-rating of RAM is different from all others in terms of 'cycle time'



That does make sense, and I would imagine that CAS timing would be considered in system-specification.



> I've never really 'dug deep' on the subject other than some minor tweaks ('guesstimates') needed for overclocking on my computer.



I do not overclock. It'd kind of defeat the purpose of owning a workstation.



> Putting different speed RAM or even different sized RAM in 'paired' slots may result in anything from failure to boot to BSOD (Blue Screen Of Death).  On (I think) all the ASUS motherboards I've used to build and upgrade computers with through the years, if there's 4 slots for RAM, they are always 'paired' A-B-A-B where if two sticks are used, they should be in both A slots, etc.



IIRC my manual only specifies a specific order which ram must be installed, not any mention of pairing. Obviously the machine does run reliably with an odd-number of memory slots filled. I just don't know if slots are shared by both processors in such an instance. So like, if Processor A has 4+8gb available, while Processor B has only 4GB available; if both processors have access to the 4gb associated with their slots while sharing the 8gb installed in Processor A's second slot; or if they both share all memory according to what is available at the time.



> So, would installing additional memory be an improvement?



I frequently get an "out of memory" error. So yes, that is the issue. Again, sometimes this is me just being stupid, and there is something to be said about learning on limited hardware, but it's pretty ridiculous at times. Plus I think excessive processing times would be a big enough deterrent to not add too many zeros without having everything just crash out on me.



> I would still run into the same 'wall', just later than before.



Well, yes! I upgraded to this machine so I could "handle anything school demands". But I ended up just putting more demands on my work, so I don't really see any net performance gain!



> One other issue is that of the capabilities of the motherboard.



Maximum capacity is 128gb. So this isn't an issue.



> It might be slow processor speeds.



I do have a good feel for processor speed as my render times are reasonable. The issue is in simulation time, and more significantly in RAM usage. For larger simulations, memory usage does start to peak out at 80-95% with very slow response, making even cancelling out a slow simulation sometimes impossible. Even ending the process entirely is sometimes impossible.

If I can't cancel a mistake without having to watch a few episodes of Pawn Stars while waiting for Houdini to crash, it puts a lot of downtime on my assignment.



> So double-check what RAM speeds are needed by your XEON processors



I think that this is a good argument for buying the system-specific RAM.



> It could also be slow hard drive speeds.  That could be the result of using IDE drives or SATA 2 drives instead of SATA 3 drives. (Don't even THINK of using external USB or eSATA drives if you want any kind of speed at all!)



HDD for files and OS is on SAS with a SSD for cache and applications on SATA3. I'd like to get an M.2 SSD for cache and put the OS on the SATA SSD, but that's not priority ATM. External USB for backup and transport only. HDD is getting around 130gb/s in hardware RAID 1 (obviously I have two drives mirrored as one), SSD is getting around 340gb/s.



> Also, for what it's worth, I have a cheap, 2MB, non-fan-cooled video card in my computer.



I have a very expensive 2gb video card (Quadro K2000). It's what came with the computer. I'm not sure how I feel about it. It's pretty lousy for GPGPU, but runs viewport adequately.

GPUs are pretty tricky in my case, actually. There is an awkward handle on the inside of my case that limits the size of the GPU I can install, though I don't really trust the overclocked gamer cards anyway. The PSU is also very, very hairpin about overage, and one disadvantage with buying a factory-built PC is that they use a proprietary PSU .. and for a Precision Workstation, they're not cheap ... at all.

There is a whole host of complications in my case, least of which is the technology is changing pretty quickly. Maxwell Render is likely to use GPU more, while Pixar Renderman is rumored to also. But what technology and to what extent they'll be using is unknown.

I also don't have a good feel for which cards perform best with OpenCL, What my OpenCL workload looks like, whether or not I want to ditch the Quadro for a GTX and what Radeon cards perform well and by what margin under OpenCL. And because I don't do much with GPGU as my card isn't well-suited for it, I also don't know what kind of memory usages I'd require.

Kinda like this idea though 

Dell CloudEdge C410x 16x M2090 GPU PCI Exansion Systems 2x PW, 4x HBA with cable

I'd have to ditch my Quadro and HD controller, but who needs a monitor or hard drive if you have 16 processing units?



> Edit: as far as buying on ebay, I've learned the hard way to stay away.



I think you've answered my questions pretty clearly actually. Considering CAS timing and other specifications, it's going to be best to buy system-specific memory from Newegg or directly from the manufacturer (or if I want to waste money, from Dell).

I bought this machine rather than building one to simplify matters like this, the engineers at Dell has already figured this stuff out.


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## jcdeboever (Jan 24, 2016)

It's a simple answer. Things to consider...  Your OS may limit you in amount of ram, so as an example using Windows, you will want the professional 64 bit version. In terms of ram, purchase the exact ram you have you currently have. If that is not possible, go to Crucial's web site and use their advisory tool. Their ram is high quality and guaranteed compatible. Match your specs. Follow the link I have provided. See, simple. 

Computer memory and SSD upgrades for Dell Precision WorkStation Precision Workstation T5610 from Crucial

Sent from my XT1254 using Tapatalk


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## SnappingShark (Jan 24, 2016)

advisor | United States (USD)

This website will give you ALL your memory options for your exact current system.


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## unpopular (Jan 24, 2016)

jcdeboever said:


> Your OS may limit you in amount of ram, so as an example using Windows, you will want the professional 64 bit version.



I am using Windows Professional.


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## bratkinson (Jan 25, 2016)

Good catch on the ECC memory, BrightByNature!   I missed the ECC part of the original post.  Putting non-ECC RAM into the computer would likely cause it not to boot up!  

In the tradition of mainframe computers, the early PCs always had a parity bit for every byte (8 bits) of memory to detect a memory error.  That extra bit cost money when buying RAM.  Somewhere along the evolution from the 8088 to 286 and 386, the parity bit got dropped from RAM more as a cost saving measure than anything else.  So, instead of the computer 'catching' a memory error and possibly retrying the read operation, it merrily goes on its way until it can no longer continue, and up comes the blue screen of death!  Fortunately, computer manufacturers such as Dell put the parity bit requirement back to reduce failures on the higher-end machines.  Good for them!

As far as using Windows Professional, I believe there's both 32-bit and 64-bit versions available.  You definitely want the 64-bit version for memory addressability.  To verify which version you have, click the <start> button, then right click the 'computer' option in the right side column of the start popup, and then left click 'properties' in the drop-down from 'computer'.  That will display which version and System Type will show either 32- or 64- bit operating system.


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## unpopular (Jan 26, 2016)

It is 64 bit.

Error correction is another reason I went with Xeon over i7. I'm unsure how frequently it's been used, it's kind of hard to know when errors don't occur. But the system feels very stable provided I'm not abusing it.


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## runnah (Jan 26, 2016)

Sounds to me like there is a bottleneck at the server node bypass output module.


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## unpopular (Feb 9, 2016)

Thanks everyone.

I just ordered 40GB from Kingston. Another 8gb to match the 8gb stick installed and another two 16 gb sticks for funzies.


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## table1349 (Feb 9, 2016)

Memory Upgrade


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## unpopular (Feb 9, 2016)

gryphonslair99 said:


> Memory Upgrade



LMAO - You seriously reminded me that I need to order my nootropics for the semester. I'm not even joking. 

All the Grade-A students are doing them!


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## table1349 (Feb 9, 2016)

unpopular said:


> gryphonslair99 said:
> 
> 
> > Memory Upgrade
> ...


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