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[Grimlocke]

The desktop APUs right now are rather limited due to the comparatively slow memory and lacking heat dissipation.  If somehow someone were to integrate a current high-end GPU and CPU then they would need a single cooler to cart off some 300 watts of heat which would be... problematic. I suspect it will be quite a while yet before high-end GPUs take up as much space and power as an integrated GPU does now.

Multithreading in gaming may finally be forced to actually be implemented properly now, what with them having 8 cores each with rather limited power (they are a modified version of the Jaguar CPUs, which is AMD lowest-end CPU made for stuff like embedded applications and HTPCs).

The annoying thing with games though is that they are generally pieced together from numerous bits and pieces, with some code as old as the first Quake game, and even fairly new code still gets written with only a single thread as its simply a lot cheaper to develop. For instance: Kerbal Space Program built its game on the Unity engine, Unity in turn licensed an older CPU-based version of nVidea PhysX, which is single-threaded as nVidea made PhysX for GPUs in the first place and clearly didn't put much of a priority into the CPU version. Which is why KSP, despite being fairly recently made for PC only, still runs its heaviest workload on a single core.

Long story short I wouldn't expect all of next years releases to have proper multi-threading quite yet.

[Miuramir]

This is changing now, with the new consoles out the big AAA cross-platform game engines will restructure themselves to use 8 cores, as that's what both the XBOne and the PS4 have.

This is an interesting point.  So far, there has been little to no reason for most users to get anything more than a quad core; so few things really use more than a couple of cores at any intensity.  But games written for the current crop of 8-core consoles will *eventually* start getting PC ports, and in general the whole toolchain for doing multiple core computing will improve under market pressure from studios and developers.  If you replace your computer every couple of years, this probably isn't a worry yet; if you're expecting things to last 5+ years it's probably something to consider. 

If I had to guess, we're drifting toward quad-core for mobile and embedded, oct-core for desktop and console as the default for power users and gamers.  I suspect there will be a plateau there for a bit, but we'll see. 

To bring this back to DF, as others have said anything but the tiniest embarks on the slowest CPUs are likely I/O bound; the limiting factor seems to be getting the data (gigabytes, far more than any cache) from main memory to the CPU and back again, every frame.  This is rare for games *or* benchmarks, which makes comparisons difficult.  Single-core performance is the next most important factor.  In general, more recent Intel CPUs and chipsets tend to be on the top end, but if you're on a strict budget may not be your best price/performance choice down lower. 

[lordpyridine]

What is your budget? I mean, for a few thousand Puget Systems can knock out monster computers with more RAM than you can count. 256 gigs of DDR3? Only the beginning.

Now, for those without a massive income, Cybertron PC can make a fantastic PC for very cheap, like under $500, and best of all you can choose exactly what parts you need. I personally recommend AMD over Intel processors, as you can get 4/5th the performace for half the price, leaving you to buy better RAM and whatnot. and don't get me started on liquid cooling...

[Putnam]

No, intel processors are way better in single-core performance.

...But really, that doesn't actually matter as much as you might think for DF. I'd definitely recommend AMD if you're on a budget. I mean, my AMD CPU is working just fine, even for DF; I ran a fort for 3 years recently at a fairly consistent 1200 FPS the whole time (nanofort, which isn't bad at all).

[Orange Wizard]

Puget Systems

I like how they explicitly state on the homepage that they don't deliver to NZ.

[lordpyridine]

But doesn't DF support multicores? In that case, AMD would win on a budget as they give more cores for less cost, and I don't think a 0.2ghz change outdoing two more cores. Hmmm... 16 core Opteron 6200? Wait... Ah bugger, the Intel Xeon has an 18 core model, so I just disproved myself. Like I could ever afford one, but I can dream can't I?

[Orange Wizard]

DF uses 2 cores at most. One of those is the rendering, which doesn't need much power at all.

[lordpyridine]

Dang. And where do you see that on Puget systems? I cant find it.

[Orange Wizard]

This page. Not the homepage. I cannot into English.

[lordpyridine]

Ahh okay. Too bad DF is only 2 core, imagine what a 64 core quad CPU with 1TB of ram could do. Besides dim the lights in your entire neighborhood when you turn it on.

[BoredVirulence]

Spoiler: I rambled on, contributed little to the discussion, and probably made my points very poorly... (click to show/hide)

APU's are a good move. The primary bottleneck in graphics is loading from RAM to the GPU. I was fortunate enough to attend a lecture about a a professor's recent research involving efficiently rendering very large models (5GB+). The majority (I think 60% or more) of the time spent waiting was from shuffling data between RAM and GPU. Not such an issue when less resources are there, but its an issue that dedicated GPU's can't solve.

I do hope AMD hasn't given up on desktop CPU's. High end FX processors actually beat high end i7's in a lot of updated benchmarks. Something about tom's hardware using the wrong RAM or something. Even if those claims were false (so difficult to tell, so many fan-boys, so much reliance on benchmarks, Intel vs. AMD could easily be Microsoft vs. OpenGL), it offers comparable performance for a better price.

Anyone claiming less cores is ideal is simply wrong. DF does use 2 threads, although the main thread does the majority of the work. More cores means less context switching from other processes. Having more cores doesn't hurt, its just not particularly helpful. Limiting one process (DF) to one core just means those individual threads are more likely to context switch eachother and compete. Frankly, I'd be willing to bet that with a large multicore machine, say 8 cores, the OS would be smart enough to realize DF's processing needs, and maintain the main thread running more by using its other cores to full advantage and servicing the other processes. Does the context switching that forces it to migrate cores actually mean more waiting than competing with its graphics thread?

Unfortunately newer processors do have less of an impact than they should. DF is very memory intensive, and it uses so much that it likely cannot properly cache that data. It probably reads from RAM more often than it should, making improvements in caches less useful.

Honestly, the ideal machine to run DF something like a custom built FPGA or ASIC, just to optimize its memory requirements. Or at least a CPU with an insanely expensive and large cache.

[wuphonsreach]

No, intel processors are way better in single-core performance.

I have yet to see by how much the Intel i7-4790K beats out the AMD FX-8350 on single-core stuff like KSP or DF.  Estimates have been anywhere from 5% to 30%.

I've been running an FX-8350 for a while now, will upgrade to the i7-4790K next week (along with a move from DDR3 1600 to DDR3 2400).  Hoping I can pickup about +50% single-core performance, but I suspect it will only be +25%.

(The i7-4790K is probably the best bang-for-the-buck if you are willing to spend ~$350 for a CPU.  It gets crazy expensive after that point.)

[Grimlocke]

No, intel processors are way better in single-core performance.

I have yet to see by how much the Intel i7-4790K beats out the AMD FX-8350 on single-core stuff like KSP or DF.  Estimates have been anywhere from 5% to 30%.

I've been running an FX-8350 for a while now, will upgrade to the i7-4790K next week (along with a move from DDR3 1600 to DDR3 2400).  Hoping I can pickup about +50% single-core performance, but I suspect it will only be +25%.

(The i7-4790K is probably the best bang-for-the-buck if you are willing to spend ~$350 for a CPU.  It gets crazy expensive after that point.)

The desktop i7s only boast hyperthreading over the i5s, which is no use for DF. The 4690K should have identical single-core performance at the same clock speed.

[exdeathbr]

Someone should get one of those websites where you can create a pc build and make the DF fortress build there.
So everytime someone ask about it we just point to the link where he will be able to just click on buy and buy the build or just change some stuff and then click on buy.

[ibanix]

Having not read most of the replies...

DF is not (to my knowledge) multi-threaded. A quad core is unlikely to be more useful than a dual core; cores will matter less than overall processing power on a single core.

DF does not actually seem to use that much memory; my 150+ dwarf fortress with a lot of space revealed is using less than 300MB of ram. Therefore you're likely to be better with faster RAM instead of more RAM. Assuming a sane amount of base RAM, like 4GB.