Hardware: Picking a New CPU for Second Life

The skeleton and brain of a computer is the motherboard and CPU.  A CPU is the Central Processing Unit. This is most like our brain.

The mother or main board is like out nervous system or skeleton. It is the large circuit board that every part of the computer plugs into, including the CPU. It holds everything together.

For detailed information on CPU’s see the video: (jump to TM 6:07 to skip the explanations and see the benchmarks.

There is a lot of jargon in the video, I’ll get the important stuff explained.

First the TL:DR, the video shows there is very little difference between the various CPU’s. When it comes to frames per second. The three tested CPU’s are about equal. However, if you are going to use Intel’s HD Graphics without a dedicated graphics card, he shows there is a difference and the 6th generation CPU wins. So, laptop people… go for 6th gen CPU or a dedicated video chip.

CPU’s

CPU’s are made by AMD and Intel, two competing companies. Debates rage daily as to which is best. For Second Life, it doesn’t make much difference which CPU you use. Some will argue that point. I can’t find any benchmarks to clearly prove the point either way. Tom’s has a forum thread where they are discussing a CPU for Second Life™. See: i7 6700K or i7 5930K for new computer build (Jan 2016). It is typical of what I’ve seen, just not much help.

Intel E5200 #1

Intel E5200 #1 – Nal: 2009 CPU, Appearance hasn’t changed much.

In that short thread the question is ‘go with top of the line 6th generation or a 5th generation older CPU?’ I’ll try to give you a practical answer that fits Second Life.

My experience is with Intel CPU’s. So, that’s what I’ll write about. Sorry AMD.

Intel names their CPU’s with a whole bunch of designators. One such is Xenon. Those are CPU’s designed for high volume data processing, usually servers, but gamers have adapted them for use where more cores help game performance. More cores are not a big plus for boosting SL performance. So, the consumer level Intel Core™ i3, i5, and i7 are the designators of interest to most of us.

Viewer and Hardware Monitor - i5-6600K & GTX 1060

Viewer and Hardware Monitor – i5-6600K & GTX 1060

From the video we found out that a 5th generation Intel CPU like the i7-5930K is about the best gaming CPU you can get, for now. But, they are selling used and new on eBay for US$450 and up. The i7-6700k is selling new on eBay for $275 and up. So… …what’s up with that? I’ll get to it.

You heard Paul in the video talk about cores. A core is what we thought of as the CPU some time ago, when a CPU had only one core. A core can add two numbers together. A single core that has lots of numbers to add has to do them sequentially one at a time. A 4 core CPU can add four sets of numbers at the same time, in parallel. Way faster. More cores are pretty much better. But, you have to use them to see an improvement. Not all apps use all the available cores. SL has been weak in this area, but it has been improving.

The i7-5930K has hyper threading. That means it is designed to switch tasks between cores really really fast. With a 6 core processor, meaning it has 6 CPU’s built into one, your computer can do 6 things at once. Six brains like six people in one package. With hyper-threading it is almost like having 12 cores, 12 people doing things. The hyper-threading makes the chip more valuable because it can do more in the same amount of time.

The i7-6700K (US$340 retail – Sept 2016 prices) has 4 cores and hyper-threads to act like 8 cores. The i7-5930k ($580 retail) has 6 cores and hyper-threads to look like 12. That is a 50% increase in cores for a supposed 50% performance increase. But, it is a 70% price increase. An i7-6950x with 10 cores and hyper-threading goes for US$1,650. Yikes!

Do more cores help with Second Life performance? Yes, to a point. The image above shows me with a viewer and monitor running. Notice one core is using to 56% of its capacity, the second 45%, third 26%, and the forth 23%. If I forced two of those cores off line, I still wouldn’t be using 100% of the first two cores’ power. So, a 5th, 6th, and more cores are not going to make a noticeable difference. Once in while they may help. If I am running Word, FRAPS, a viewer, Chrome, and etc. then more cores could help. But, the cost to benefit ratio falls apart. The 3rd and additional cores just aren’t helping that much.

I can have 4 cores doing a lot, working hard but nowhere near their limit. Or 12 or 20 cores loafing along doing very little. Actual performance may be ‘numerically’ superior, like more FPS, but, until you can see a difference, is it a difference?

More pages, links below…

4 thoughts on “Hardware: Picking a New CPU for Second Life

  1. Honestly… best to wait for AMD’s Zen in October.

    And it’s important because AMD hasn’t seriously tried to compete in CPU for gamers in a long while and they always offer at lower price than Intel’s. Now they are.

    It could be a flop… but it also could be great. Tech experts believes their CPU FX model with 8 cores and 16 threads are to be priced around $250-$350. Spec that was on par with Intel’s Broadwell-E, which is priced at $1,100 currently.

    But then you’d have to get a new motherboard for it, but there’s a good chance that price difference with Intel could pay it off for that new AMD motherboard.

    • Thanks for saying.

      AMD could choose to compete in gaming. That would be good. From what I am reading scientists in places like CERN are excited about Zen. But, I’m not hearing much about gaming.

      They are going to smaller size (14nm) and packing in more cores (32). Historically more cores has forced down clock speed. We’ll have to see if they can solve some problems and provide more fast cores.

  2. Second Life viewers require you to get the fastest CPU on a per core basis (and a dual core or better; but more than 4 cores, or “hyperthreading” won’t do any difference whatsoever).

    Why ?
    Because the SL viewers’ renderer (unlike almost all recent games) is a mono-threaded task running in the main loop of the program, and the latter will consume one full core long before any modern GPU (such as the NVIDIA GTX 970 or better) gets saturated: the bottleneck is at the CPU level (and even at the CPU core level).

    Some graphics drivers (such as NVIDIA’s proprietary one) can use multi-threading by themselves, even when their OpenGL functions are called from a single-threaded software: enabling multi-threading in one such driver will get you a 20-30% fps boost at the cost of the consumption of a third to one full core processing power (meaning the viewer will consume 1.3 to 2 full cores while rendering a fully rezzed scene).

    During rezzing, the viewer will also make use of threads to fetch, decode and cache the textures and meshes, and up to half a CPU core may be consumed while it happens (thus why a quad core will give you slightly better results than a dual core CPU).

    It means that the best processor for Second Life is a quad-core with the highest clock speed * IPC (instructions per clock) product. A Core-i5 with the best overclocking capability is for now the best choice (at least until AMD comes up with a Zen CPU that can compete with Intel on this front).
    My 2500K (Sandy Bridge Core-i5) gives wonderful results at its 4.6GHz overclock speed (and probably equivalent results to what a Skylake would provide, given the latter, while providing a somewhat better (~20%) IPC, got a somewhat lower (~20% as well) stable overclock speed).

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