Creating a benchmark for Multiboxing Systems.

[Sina]

http://img187.imageshack.us/img187/2480/img0119vc7.jpg

A little introduction : I work for a company called Doghousesystems.com and i have had a few customers who want a "cream of the crop" multiboxing system. As usual we started doing some testing with regards to what hardware do we need to setup a performance curve in relation to multiboxing customers.

Here is what i have come up with thus far:
For all practical reasons i am guessing that most multiboxers run on 2 monitors
Monitor 1 : is on 1280x1024 with all settings on "high" and is only running your main account
Monitor 2 : is running 4 clients of 800x600 with all settings on "low"

Edit: All clones are set to max fps 15 and the main account is set to uncapped. So our numbers should turn out like this:
GTX295 on i7 965 : 80/15/15/15/15
GTX 280 on i7 965: 75/15/15/15/15
ect...

Affinity is set to default ( for stability and there are so many different methods i figure to keep the playing field simple and untainted id leave it alone. )

I took all 5 accounts to nexus ( farthest western flight point ) and flew all 5 accounts ( using /timetest ) to howling fjor ( farthest flight point to the east of northrend )
"why northrend?" Because it seems to be the most taxing zones on your system.

the /timetest removes all variables and keeps your camera angle still so that you can get a repeatable framerate for the sake of benchmarking.

I have done this test now with multiple builds including all varations of:
i7 920 940 965
gtx 260
gtx 280
gtx 295
gtx 285 ( pre production)

ati radeon 4850
ati radeon 4870
ati radeon 4870x2 ( no, there were no changes thus i stuck with single card configs )


I am still in the middle of testing all this but this is only phase 1. Phase 2 will be adding different variations of hard drives including:
INTEL 32G SSD
OCZ SSD
WD Raptor
WD Vraptor
WD 7200 RPM drive ( black series )

ect.

along with the different storage settings i will try to change some display settings to see how we can optimize each frame and push out as much as we can out of our systems. Or future systems for that matter. I also plan on creating a solution for those multiboxers who are looking at purchasing a system in the future that want to multibox on a single PC. Yes i did this in the past but this will be far superior as i now have acess to far more resources.

My main reason for this post was to get your input on my "multiboxing benchmark", are you satisfied with my method? What are your suggestions?

Thanks gents/ladies ! :) Happy Boxing.

Preliminary scores:
http://img401.imageshack.us/img401/7762/img0112lo0.jpg
http://img187.imageshack.us/img187/1750/img0122rv9.jpg

[Freddie]

I think this is a great idea, and your results will be helpful to lots of people.

I'd like to suggest one change in your methods. I think you should set affinity to all cores, in other words, every instance of WoW should be able to run on cores 0, 1, 2, 3, 4, 5, 6, and 7.

Here's why. Most programs don't set their own affinities. In other words, they leave the operating system free to assign their theads to any and all cores, which gives the operating system maximum ability to optimize performance. This is the "real" default affinity, and it's the same as what I just said you should set deliberately.

But WoW isn't like those normal programs. For some reason, Wow takes deliberate action to set its own affinity to only cores 0 and 1. That means no matter how many instances of WoW you're running, it's restricted on a quad core to using (at most) half the CPU. It's the same two cores for every WoW no matter how many you run.

Nobody with a quad core should multibox that way. Obviously everyone wants their WoWs to make use of the whole CPU. But you're testing that way with just two virtual cores.

So I suggest using the "real" default -- the natural operating system setting -- for test purposes, with all threads free to run on all cores.

[Sina]

I'd say use the wiki...... but nobody appears to use it anyway.

Please point me to where the wiki shows up to date benchmarks with relation to 5 boxing on 1 pc... Also where in the wiki does it show the optimisation of different harddrives and varaiations of current SSD's . I do use the wiki but i can't seem to find these features. Hence the post.

[Sina]

I think this is a great idea, and your results will be helpful to lots of people.

I'd like to suggest one change in your methods. I think you should set affinity to all cores, in other words, every instance of WoW should be able to run on cores 0, 1, 2, 3, 4, 5, 6, and 7.

Here's why. Most programs don't set their own affinities. In other words, they leave the operating system free to assign their theads to any and all cores, which gives the operating system maximum ability to optimize performance. This is the "real" default affinity, and it's the same as what I just said you should set deliberately.

But WoW isn't like those normal programs. For some reason, Wow takes deliberate action to set its own affinity to only cores 0 and 1. That means no matter how many instances of WoW you're running, it's restricted on a quad core to using (at most) half the CPU. It's the same two cores for every WoW no matter how many you run.

Nobody with a quad core should multibox that way. Obviously everyone wants their WoWs to make use of the whole CPU. But you're testing that way with just two virtual cores.

So I suggest using the "real" default -- the natural operating system setting -- for test purposes, with all threads free to run on all cores.


Noted, i will add this to the benchmark.

[weeep]

Why 1280x1024 for main? I don't think that somebody willing to buy a computer capable of 5boxing, cant afford a better monitor. Try AT LEAST 1920x1200, or even better 2560x1600. Video performance and lack of video memory while 5boxing is really hurting fps on real systems.

[Yo-Yo Freak]

Why 1280x1024 for main? I don't think that somebody willing to buy a computer capable of 5boxing, cant afford a better monitor. Try AT LEAST 1920x1200, or even better 2560x1600. Video performance and lack of video memory while 5boxing is really hurting fps on real systems.the average person will only be using a 1280x1024 monitor, MAYBE a 1920x1200 monitor but that is highly unlikely, and a 2560x1600 monitor for your main? please... if you think about it a 24" monitor is already pushing it to be able to view your alts as it is. nobody in there right mind would use a 30" for there main and a second monitor for there alts, they would be so far out of your pereferial vision that you would probably have to swivel in your chair to look at it. just stick with 1280x1024 and maybe 1920x1200, anything bigger than that would be a wast of time on your part IMHO.

other then that i agree with Freddie, wow will default to the first two cores, logical or physical. set the them to default to all cores (0-7 on the i7 CPU), that will help to maximize performance output.

everything else looks great, can't w8 to see your results! keep us updated ^_^.

oh and Doghousesystems has some very nice looking stuff, looks like its very high quality work :thumbsup: .

~YYF

[Shaitan256]

I'd say use the wiki...... but nobody appears to use it anyway.

Seems like that, but I can't understand that, it's such a huge Knowledge Encyclopedia about Multiboxing, I look it up everytime I've got something in mind, that oculd be helpful, if it's already in there I look through it if not I'll waste your time with reading my Posts *muhaha*^^

[Sam DeathWalker]

This is how to maximize your system:

You dont need raid.

http://www.anandtech.com/mb/showdoc.aspx?i=3471&p=9

Get the gigabyte (extreme version) then.

http://cgi.ebay.com/GIGABYTE-GA-EX58-EXT�1QQcmdZViewItem

Get a Veloraptor (1). Put 24G on the board. 920 should be suffieicent cpu (assuming just for 5 boxing wow if you doing ray tracing or seit or other stuffs then get better).

Get 280 or whatever high end video card you like (1), NOT TWO. If you want to burn money just get a better single card, not two.

SPend yur monies on FIRST QUALITY 24G of ram.

64 bit OS and yur done dont waste on raid, SSD or anything else. Put the whole wow folder (everything) in ram before you start (make yur ram a ram drive for like 10G of it, after to shut down you have to read the whole ram drive back to the raptor so that if any writes were made they will stay). Wham you will get the best frame rates possible, and not waste monies where not needed.

You will get unreal framerates cause of the 28GB/s that the i7 can move data at. TWENTY EIGHT GIG A SECOND thats how fast you will be moveing data from your ram to your cpu. I mean lol ... you will never access the hard drive during play, because the entire wow folder is in your ram drive.

SSD drive is 3G/S IF THAT AT BEST, raptor is slower.

Your Ram 28G/S

This tells it all:

http://www.legitreviews.com/article/824/4/

My best system is 11G/sec. My others are like 8G/sec and there is a big difference between the systems (my 11G/sec system closes out 5 wows FASTER then a quadcore 4G/sec closes out ONE wow). I can't imigane have a 28G/sec is going to be. You can hit exit and hit the desktop almost instantly I bet.

You win.

Read thread: Nvidia GTX 295 - good gawd!

the 285 would be my choice but high end ati is good also. Silencer comments in the thread are my belief also.

Also you cannot use FPS that is more then your monitor refreash rate. If you have a FPS of 100, and your monitor is 75HZ then your video card just throw away the 25 extra frames it had to calculate that second. Get a 120HZ monitor if you have money to burn, THEN set your max FPS at 120 and you will see full effect of your video card. 120 FPS on a 60HZ monitor is you video card doing 2X more work then is sent to your eyes ....


The I7 and having the whole wow folder in ram is what is going to make yur fps go way up.

I have 1600X1200 on main and 1280X960 on the 5 other computers (Im the 26 boxer guy), my monitor can do the 1920 X 1200 but I need 4:3 so I can copy UI's to all.

I guess a flight is as good as anything else.

You won't see much difference between the high end video cards. The Memory bandwidth is what makes or breaks you.

Ya Im 60fps on main and limit of 30inforground 5back on the other 5. I run all in fullsceen and no tiles.

[Clanked]

The benchmark I really want to read about, is the amount of ram.
6GB vs 12GB in dalaran. Is 6 really enough?

Also tri display setups.
Can a secondary 4870 card support two 1680x1050 monitors running 2 clients each with the primary card running the main client only?

[Sina]

i will do a few 12g v 6g ddr3 tests. I can also do corsair vs kingston ect.

added some pictures of whats going on. will have a full whitepaper soon.

[Sam DeathWalker]

Excellent effort I see nothing but positive coming from this.

[Freddie]

Yeah this is great.

/salute Sina

[zanthor]

As to displays - the average cheap older panel is 1280x1024, most users are going to have two.

MANY of us have higher end systems and I can personally say that dual 22's is perfectly playable and I have no issues with my side-vision having them set @ 1680x1050.

I like the testing method, I'll have to give this a shot on my system tonight as I've got three AMD chips available for the moment... AMD Phenom 9600 (2.3ghz), the 9950 (2.6ghz) and the new phenom II @ 3.0GHZ should be arriving this afternoon!

[Sina]

I will setup on the main post a "how to replicate" for the benchmark so we all have the same numbers. Will help us deliberate our ultimate setup :). AMD numbers will be interesting to see.

[Owltoid]

Ouch, so when my new rig comes in (i7 920, GTX 260) I'm only looking at FPS of 40, 15, 15, 15, 15? I was really hoping for more like 60, 25, 25, 25, 25 though I really don't cares about my slaves getting much above 10 (and will probably set their limit as such)

[Sina]

well it just depends on what settings you use. i have not messed with affinity ( which will increase your frames ) and i have capped the slaves at 15. I am sure you can push it a bit harder but im again , trying to set a level playing field to test all cards and cpu structures.

[-silencer-]

I'm interested in this thread, so here's a few comments..

- Interesting lack of difference between a 4870 and x2 4870 (does this mean two 4870 videocards or a 4870x2 videocard? which 4870.. 1GB or 512MB?).

- Sam's post is something I mentioned months ago, but it's got a few major drawbacks:
----- 24GB of DDR3 is going to cost around $2000 in RAM alone (Crucial's 3x4GB (12GB) ECC/registered module kits are $960 each), so good luck finding the memory or even a motherboard that supports ECC/registered modules without issues. (Yes, many claim 24GB support, because that's Intel's X58 spec, but the mobo doesn't have proper BIOS support for it yet.) 2x RAID0 30GB SSDs will cost under $200 and offer better performance than Velociraptors. Also, since the problem with fetching /data isn't bandwidth! It's access time, and although the ram drive will be faster, the price-performance & *hassle* isn't even close to the benefit of SSDs.. on to the hassle aspect:
----- *EVERY* time your computer is turned off or rebooted, you have to reload your ram drive with the WoW/data directory. That's why I was hoping for a new Gigabyte i-RAM drive supporting ddr2 modules and at least 16GB - battery backup while using system memory for data. Looks like the original i-RAM didn't sell well enough to encourage them to make a newer version - maybe because using a PCI slot sucks, 4GB is small, DDR1 is more expensive than DDR2, and SATA 1.5 is slower than SATA 3.0. The i-RAMBOX was an improvement, but still needed more max capacity, DDR2, and SATA 3.0.

- For the flight path, I would have picked something that flies over/near Dalaran - at least enough to pick up on the massive amount of objects/textures in the area. The primary downside of this is that the fps will be dependent on how busy Dalaran is with players at a given time.

Nice data though.. it's cool to see actual tests being done..

[Sina]

I'm interested in this thread, so here's a few comments..

- Interesting lack of difference between a 4870 and x2 4870 (does this mean two 4870 videocards or a 4870x2 videocard? which 4870.. 1GB or 512MB?).

- Sam's post is something I mentioned months ago, but it's got a few major drawbacks:
----- 24GB of DDR3 is going to cost around $2000 in RAM alone (Crucial's 3x4GB (12GB) ECC/registered module kits are $960 each), so good luck finding the memory or even a motherboard that supports ECC/registered modules without issues. (Yes, many claim 24GB support, because that's Intel's X58 spec, but the mobo doesn't have proper BIOS support for it yet.) 2x RAID0 30GB SSDs will cost under $200 and offer better performance than Velociraptors. Also, since the problem with fetching /data isn't bandwidth! It's access time, and although the ram drive will be faster, the price-performance & *hassle* isn't even close to the benefit of SSDs.. on to the hassle aspect:
----- *EVERY* time your computer is turned off or rebooted, you have to reload your ram drive with the WoW/data directory. That's why I was hoping for a new Gigabyte i-RAM drive supporting ddr2 modules and at least 16GB - battery backup while using system memory for data. Looks like the original i-RAM didn't sell well enough to encourage them to make a newer version - maybe because using a PCI slot sucks, 4GB is small, DDR1 is more expensive than DDR2, and SATA 1.5 is slower than SATA 3.0. The i-RAMBOX was an improvement, but still needed more max capacity, DDR2, and SATA 3.0.

- For the flight path, I would have picked something that flies over/near Dalaran - at least enough to pick up on the massive amount of objects/textures in the area. The primary downside of this is that the fps will be dependent on how busy Dalaran is with players at a given time.

Nice data though.. it's cool to see actual tests being done..THanks!

I am not completely done with the numbers im hoping to have everything crunched and presentable come monday. On top of that we will have a doghouse solution for our end result with a 3 year warranty.
I am guessing the bang for your buck with end up being a 920 with a single 4870 ( 1gig) with 6 gig of ddr3. Still working on the storage solution, looking forward to seeing these results and will relay to you all soon!

[-silencer-]

THanks!

I am not completely done with the numbers im hoping to have everything crunched and presentable come monday. On top of that we will have a doghouse solution for our end result with a 3 year warranty.
I am guessing the bang for your buck with end up being a 920 with a single 4870 ( 1gig) with 6 gig of ddr3. Still working on the storage solution, looking forward to seeing these results and will relay to you all soon!
These are the specs I'd expect to see on a bang-for-the-buck 5-boxing machine:
- i7 920
- X58
- 6GB DDR3 (minimum!)
- HD 4870 1GB (although at the current price, the GTX 280 is also looking very nice.. and I like the GTX 285 as well)
- *quality* power supply.. SeaSonic or SeaSonic-based (like the Corsair 520w/620w models). The CWT-based Corsair 1000w is also very nice, but not even close to necessary for a bang-for-the-buck machine. SeaSonic/Corsair 620w will run this machine with plenty of power to spare.
- Large hard drive.. this shouldn't be a place to cut corners. 1TB 7200rpm is under $100, and it's plenty fast. A lot of storage space is something that shouldn't need to be added later for any machine costing $1500+.
- SSD.. here's the performance for multiboxing. 30GB is more than enough space for WoW/data, and it's also under $100. Since we only need it for fast random reads, we don't need a high performance drive. Even the worse SSDs are much faster than a Velociraptor for our use.

[Mercurio]

This is all very cool.

Sina PMed me about a month ago when I was looking for advice building a system. We figured out I live only about 8 minutes from Doghouse Systems, so I stopped by, talked to Sina, some other engineers, and even the owner. It was great to talk to another multiboxer who really understands our rather unique requirements and someone much more knowledgable about computers than I am. Doghouse was already thinking about the needs of multiboxers and I got to be a test case. I got to ask all sorts of questions about performance under different scenarios and over the next week or so Sina ran a number of tests and shared the output. It was nice to have him do the leg work on any reasonable configurations I could come up with. In fact, everyone at Doghouse seemed very interested and happy to help. We went back and forth on a couple of components, but In the end, I configured a pretty nice system and placed an order. The system should be ready next week (sweet!), so I'll be happy to add my experiences to the pile of data Sina is creating.

[Owltoid]

.......
- 6GB DDR3 (minimum!)
- HD 4870 1GB (although at the current price, the GTX 280 is also looking very nice.. and I like the GTX 285 as well)


Some users on this site are mentioning 6GB isn't enough for the busier areas (Dalaran, Wintergrasp). If you're going to spend the money somewhere, do you think it would be better to get the extra RAM (12GB) and the lesser video card (GTX 260)?

Otherwise you basically mentioned my computer :thumbsup:

[Clanked]

I'm interested in this thread, so here's a few comments.. ----- *EVERY* time your computer is turned off or rebooted, you have to reload your ram drive with the WoW/data directory. That's why I was hoping for a new Gigabyte i-RAM drive supporting ddr2 modules and at least 16GB - battery backup while using system memory for data. Looks like the original i-RAM didn't sell well enough to encourage them to make a newer version - maybe because using a PCI slot sucks, 4GB is small, DDR1 is more expensive than DDR2, and SATA 1.5 is slower than SATA 3.0. The i-RAMBOX was an improvement, but still needed more max capacity, DDR2, and SATA 3.0.

ACard's ANS-9010 Serial ATA RAM disk
http://techreport.com/articles.x/16255

Enjoy.

[Sam DeathWalker]

I say wait 6 months.

Yes you are looking at $1800 for 24G ram, today. Its just going to get lower and lower in price. The A card again is on the Sata buss, which is 3G/Sec compare to 28G/Sec of the I7 system memory.

Well if Wow requires a LOT of tiny packets vs. some a bit larger packets then access time will be more important then transfer rate. Would be nice to actually know the number and size of files it needs to access during gameplay, and if they are stored sequentially.

I think it is safe to assume that zone textures would be stored all together not needed multiple accesses ... Why would orgainize the textures in anything else but a zone by zone sequence?

No doubt SSD will be more cost effective. But most threads I am posting in assuming unlimited funds not "best bang for buck".

You spend $400 on the Drive and then $400 or so on 32G ram, so you are almost at 1/2 the price of the onboard ram already. You have 8 slots so you have to get 16G (pushing it) or 32G ...

I don't consider the "hassel" of writing the wow folder to a ram drive and back again as any consequence.

[-silencer-]

I'm interested in this thread, so here's a few comments.. ----- *EVERY* time your computer is turned off or rebooted, you have to reload your ram drive with the WoW/data directory. That's why I was hoping for a new Gigabyte i-RAM drive supporting ddr2 modules and at least 16GB - battery backup while using system memory for data. Looks like the original i-RAM didn't sell well enough to encourage them to make a newer version - maybe because using a PCI slot sucks, 4GB is small, DDR1 is more expensive than DDR2, and SATA 1.5 is slower than SATA 3.0. The i-RAMBOX was an improvement, but still needed more max capacity, DDR2, and SATA 3.0.

ACard's ANS-9010 Serial ATA RAM disk
http://techreport.com/articles.x/16255

Enjoy.
AWESOME! That's EXACTLY what I've been looking for! (The only comparable model I saw was over $2k, without memory.) This thing is perfect! $380 for the unit, and $220 for 16GB of DDR2! More than enough for the WoW/data directory.

[Sam DeathWalker]

You know you could get a 16G skulltrain: MB $500

http://cgi.ebay.com/Intel-Motherboard-D5400XS-Skulltrain_W0QQitemZ270336937639QQihZ017QQcategory Z45090QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

16G ddr2 ram is only not much $340 (in 4G sticks)

http://cgi.ebay.com/LOT-OF-4-Samsung-D2-800-4GB-ECC-FB-DIMM-Original-Memor_W0QQitemZ380099304870QQihZ025QQcategoryZ1114 25QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

And just put ONE CPU in the SKulltrain.


Seems better then the SSD ....

[-silencer-]

You know you could get a 16G skulltrain: MB $500

http://cgi.ebay.com/Intel-Motherboard-D5400XS-Skulltrain_W0QQitemZ270336937639QQihZ017QQcategory Z45090QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

16G ddr2 ram is only not much $340 (in 4G sticks)

http://cgi.ebay.com/LOT-OF-4-Samsung-D2-800-4GB-ECC-FB-DIMM-Original-Memor_W0QQitemZ380099304870QQihZ025QQcategoryZ1114 25QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

And just put ONE CPU in the SKulltrain.


Seems better then the SSD ....
16GB in Skulltrail.. 12GB minimum is required for WoW/data if you're still thinking of making a RAM drive.. that leaves 4GB for the OS & applications? Yeah, I'll take the better option - Acard ANS-9010 RAM-box with 16GB (or 32GB.. or 64GB) of DDR2 in RAID0, and still have 12GB of DDR3 RAM for my system. This Acard device is the next purchase on my list.. *after* I get the case built on my new machine. (case design is done, but I'm out of town both of the next two weekends..)

[Sina]

Skulltrail.... i have one laying around im sure, but how can the price of skull trail and 2 core 2 series processors come even close to being justified to an i7. I am just taking a stab here but im almost certain an x58 + 920 is better then any skulltrail config.

I guess that is the point of all this testing.... to find out :)

Sina
Multiboxer Mythbuster.

[-silencer-]

Skulltrail.... i have one laying around im sure, but how can the price of skull trail and 2 core 2 series processors come even close to being justified to an i7. I am just taking a stab here but im almost certain an x58 + 920 is better then any skulltrail config.

I guess that is the point of all this testing.... to find out :)

Sina
Multiboxer Mythbuster.
Eh, Core i7 isn't quite as massive of an improvement over Core 2 that Core 2 was over P4. Two quad Core 2 CPUs are still a force, and that many physical cores will likely overcome the i7 965's architectural advantage for heavily-multitasked applications. i7 is a slick improvement over Core 2, but it's still an expensive platform due to memory and motherboard prices over Core 2. Skulltrail is a unique beast, but like I said earlier, the time to pay premium money for it was a year ago.. not today when it's still the same price and the competition is much closer.

Which machine would I trust to handle 10-boxing with higher fps.. a Skulltrail 16GB system with 2 quad cores, or a 12GB Core i7 965 system? My bet is on the Skulltrail. With fewer instances of WoW, the difference isn't likely to be as great.. and may actually be worse under 5 instances. Pure speculation.. it'd be a fun test anyway.

[Sina]

skulltrail has a few issues though:
1) PCIEx 1.0 .... not sure why that ended up being the final slot
2) DDR2 FBDimm

How can you compare that to 2x pciex2.0 and tripple channel ddr3

just seems .... off, idk.

Didnt have time today to test it but i hope to get around to it

[Sam DeathWalker]

If you plan only 5 wow's 4G should be suffiecent for the OS and the applications, WoW is like 1/2G each iirc.

If you know that you will be in WotLK then just put in the newer data files (what 5G?), if you going to play in BC then the first 7G of data files. Wouldnt be hard to know where you plan to play that day. Some hassel ya but ...

[Nitro]

.......
- 6GB DDR3 (minimum!)
- HD 4870 1GB (although at the current price, the GTX 280 is also looking very nice.. and I like the GTX 285 as well)


Some users on this site are mentioning 6GB isn't enough for the busier areas (Dalaran, Wintergrasp). If you're going to spend the money somewhere, do you think it would be better to get the extra RAM (12GB) and the lesser video card (GTX 260)?

Otherwise you basically mentioned my computer :thumbsup:

I'm running vista 64 with 8gb of ram and in Dalaran it is not uncommon to see my 5 clients go over 7gb of ram used.

I run two monitors at 1600x1200, the main client is 1600x1200 and the 4 alts are 800x600

If I was to build a new system anytime soon I would go with nothing less than 12gb of ram.

[Sina]

Benchmarking has been done, i will be posting the results soon.

[Yo-Yo Freak]

Benchmarking has been done, i will be posting the results soon.Sweet! can't w8 to see them!! ^_^ this will probably go a long way to what i chose when i build a new system :)

~YYF

[Moorea]

Benchmarking has been done, i will be posting the results soon.... Post it ?

[Clanked]

If I was to build a new system anytime soon I would go with nothing less than 12gb of ram. Isn't that often the maximum amount of ram on a desktop board?
That is a firmware limitation only.
The x58 chipset can support higher than that, but the motherboard makers themselves are not at the present time.

In fact, with the first batch of i7 motherboards to hit the market, they required a firmware update just to support 12GB, even though they were labled 24GB capable.

[Noids99]

Not to mention the lack of non ECC 4GB DDR3 RAM modules available.