[Josephus Holt]

We're looking at putting a machine together to try to speed up these renders a bit

I read somewhere that a 16 core machine loses its effectiveness per core a lot more than an 8 core machine....I think it said that a 16 core has about a 67% per core efficience as opposed to the 8 core machine which is in the mid 80's %. I don't know enough about all this if that is an across-the-board hardware limitation or if that is software related. Does anyone know about this....NL???

The real question for me is as far as using Maxwell Render is concerned, is a 16 core machine as efficient (or more??) than 2-8 core machines (considering all other factors like cpu and ram speed being equal)?

[Bubbaloo]

There are pros and cons.
Remember getting multiple machines means getting multiple software licenses, like OS.
In our office, we have quad core qx6700's and I use a dual quad Xeon 5355. Two of those QX6700's can render faster through coop than my 8 core. So I think you do lose some efficiency because of hardware bottlenecks (communication between processors).
I would suggest getting 4 quad cores, or maybe 2 dual quads, but you might not get the bang for your buck putting together a 16 core.

[Josephus Holt]

Thx Brian. I do have 2 licenses so maybe two 8 core machines would be the way to go...might have to wait a bit till prices go down more.

What are the RAM requirements of rendernodes...if say, you need 8GB ram to render out a particular scene, would you need that much in each machine if you're using 2 machines?

just got a quote for a 16 core machine...over $15K. Definitely more cost effective to go with two 8 core machines

[Brett Morgan]

Found this yesterday, not that pretty but it gave me a chubby

http://helmer.sfe.se/

Brett

[sjyie]

As you know, 2 thread is not 2 times faster than 1 thread.
Assuming the second thread gives 90% boost, 8th thread adds only 48%, and then using 8 core is faster by 5.7 times than using a single core.
And using 16 core is faster by 8.1 times than using a single core.

When you have a 8 core system and render an animation, it would be better to run 8 scenes concurrently with a single thread for each scene than rendering each scene in order with 8 threads, if the memory is sufficient.

[deadalvs]

a little input
it's not JUST about speed, but also about max memory capacity.

if you go for multiple 6600 / 6700 you'll have to consider that there's not many mobos supporting more than 8 gigs. investing in future you may consider going straight to 16 gigs if you'll have that complex scenes or will render or just want to keep up with time.
there will be a time where just the OS will need 128 gigs of ram as base...

at the moment, certainly the best bang-per-buck can be achieved using multiple overclocked 6600s, but licenses and OS costs add up too. plus most of the time you're not actually rendering final images, but rather previewing at lo-res or render material samples over and over again, which will lead to the desire for one very powerful machine without actual need for networking.

i'm still not sure if network-rendered previews are supported in studio, but i thinking about it for half a second it seems to make no sense when having to access large texture sets from one network drive to multiple nodes/servers.

* * *

there is no answer which is best. honestly you should try go analyze your basic workflow and find out what cpu-power peaks you need for deadlines. everything above the max peaks is just thrown out money, especially in the WIP phase.

there's some sort of moore's law (we need a new name for this) that the final 20% more speed for a workstation makes it cost the double than just the «very good» model. it's so complicated since this balancing act is non-linear or rather exponential.

but a VERY good rule of thumb is:

choose the best model of apple's current hardware (mac pro at the moment) and go out and buy all the components and build it yourself. add a good graphics card and you're totally okay with 30% less costs than an actual mac pro.

need more power? buy two.
need even more power but work in a risky field like freelance? go renderfarm.

* * *

on my last office/job i had i brought my own overclocked quadcore 6700 since they didn't provide me with a good computer and i'd rather bring my own computer and work happily and efficiently than just cursing and having my computer get dusty at home anyway. two to three years is the time you'll want to use the hardware or at least have it totally payed off.


and an other thought
dreaming of the ultimate machine like that 32-core here i've seen at siggraph ( that runs all cpus under ONE OS ! )
http://www.hpcsystems.com/AMDQuadOpteron_A5808-32.htm
may certainly be also a competitive option when starting at 20K $ with the expenses of just one OS and no network stuff and no admin stuff, but keep in mind that there may come some GPU based rendering engines (maybe on cuda platform) soon (hopefully maxwell too), rendering just on GPUs and leaving your new pc behind by a factor of 50 or 100 in rendering speed.
so planning long-time investments for 2-3 years to the future may be well thought of in every aspect.

this last point with GPU-based rendering is a good reason for me to wait for any other major investment other than a tricked-out new-gen graphicscard.

it's frustrating, i know.

[Josephus Holt]

It does indeed look to me to more and more that the MacPro is the way to go at this time....keep getting the feeling like I've sat down at a poker game with the ante going up all the time

[deadalvs]

i feel your pain !



but it's so impressive... i have an 8 core mac pro 3 GHz here right next to me and i don't hear it at all... no matter how long or hard i render. it feels so super-engineered !

once you have one of those babies you will be amazed...

plus you have one of the most beautiful computer cases ever standing around .. - well .. but even being a mac, it WILL collect dust too !

[deadalvs]

but i'd also look into linux if you think about buying one or two nodes only for rendering on.

something like ubuntu that you can download for free and works just like a mac.
http://www.ubuntu.com/getubuntu

i've had the chance to use linux a little in school this term for apple's shake and massive (yes, massive ! ) and coming from a mac background it's basically the same.

now saving 150 $ or more per OS per node is certainly cool or can be invested in more ram or something else.
(( if you build just nodes to render on don't forget that you don't need any fancy graphics card since it's not used when rendering. you certainly know this but there's still people around that believe in this. ))

PLUS if you go for ubuntu or something alike you can go 64 bit and you'll never have problems with virae, just like on a mac! plus it is a very very stable OS !

* * *

an other point of view in case you cannot/don't want to afford a mac pro:
reasons not to go for it:

seeing you stuggling with a limited budget i'd personally recommend overclocked 6600s or 6700s. reasons:
• very cheap overall hardware --> 1000 to 1200 $ per node (1 cpu, 4 cores)
• the wholy system costs about the same as ONE of the latest quadcore cpus alone that are built in the newest mac lines... and there you'll need two to even get started.
• you can easily find a mobo up to 8 gigs of ddr2 800 ram
• with just a little better fan you can overclock from 100% to 125% speed and you have about the same speed as one of the newest quadcore xeons.
• knowing that going from one quad xeon (4 cores) to a dual quad xeon (8 cores) you have to know that you'll not get 200% speed increase but around 160% in average or a little more. so you have (overclocked) about 70% the speed in one box than an octo with just a third of the overall price.
• plus if your system dies for any reason (which is doubtful, but just to complete this list), you didn't invest a lot of money. (or if there comes a supercheap superfast renderer standard next year, who knows)
• the only negative point is that you'll have to build the rig yourself or invest some money to get it done by someone or your computer store.

[Josephus Holt]

Thx for the thorough comments...I really like the idea of putting a machine together myself...I've put a couple of pc's together over the years and was both times amazed it actually worked

I've actually been on pc's for about 20 years...since my first screaming 386-33 mhz with 4mb ram However, my son just switched to a Mac and he loves it and I've been thinking for my next machine to go that way myself since all my apps except Photoshop will run on Mac...I'll just have to load Windows on it to run Photoshop.

Just checked out roughly the cost to upgrade my pc to a a Core 2 Quad Q9550 (overclock to 3.66 GHZ or maybe a tad more?) with 8 GB ram for about $800 to $900. According to the Benchwell tests that would give me a 4X increase of speed over my current AMD X2.