Considering I actually have a four year old 2600K @4Ghz, it would be nice if they included an actual comparison.
Considering I actually have a four year old 2600K @4Ghz, it would be nice if they included an actual comparison.
http://anandtech.com/show/9483/intel-skylake-review-6700k-66...
Also interesting is that they found a decrease in gaming performance at 3.0ghz vs Haswell. Now, if Skylake could be expected to maintain higher frequencies than Devil's Canyon chips then the slight (3-5%) decrease could be overcome - but a Devil's Canyon i7 (the 4790k) has the same 4.0ghz base frequency as the new i7-6700K, and what looks like the same turbo frequencies.
25% faster clock-for-clock would probably fix this in most of the games I care about, and that might be enough to get me to upgrade.
I guess everything interesting has to run on a GPU nowadays.
In all my years of building PC's I can't remember a time when a nearly 5 year old machine would still run all everything I wanted to run, on the one hand that's cool on the other barring some shakeup it looks like the days of must have upgrades every year seem to be halting (for now).
Then again, I'm often memory bandwidth bound even when using just SSE. If the memory can't deliver enough data to work with, there's bound to be a performance ceiling.
Also, it is unlikely that you are actually memory bandwidth bound unless you are looping through linear memory on every core. It is fairly tricky to make useful software that is not memory latency bound.
So I don't really think it's that misleading. It's the go-to instruction.
> Also, it is unlikely that you are actually memory bandwidth bound unless you are looping through linear memory on every core.
Well, that's what Intel vtune says. If I'm processing stuff at total bandwidth of 30 GB/s, I tend to believe it. Each core is dual issue, so with SSE you can process up to 32 bytes per cycle per core. When you have 4 cores at 3.5 GHz, that adds up. The CPU beast can consume an order of magnitude more data than DRAM can supply, even with just SSE. So you can do a lot of operations on the data and still be memory bound.
That is not a true generalization at all. Maybe you are doing image compositing, but fma instructions are not so heavily used that they can be thought of as the single workhorse of a processor.
Well, indeed, a lot of cycles are lost for moving the data around, branching, waiting for memory. But when it comes to floating point computation, well, FMA is really common. In floating point inner loops it's just so usual to need to do "x := x + a * b".
I didn't say single workhorse of computer, but for DSP type of stuff FMA rocks. Dot product, matmul, even fft -- a lot of FPU heavy computation directly benefits from FMA.
Anyways, even without FMA, you can do a lot of ops per value and still be memory bound.
If you want upgrade, buy watercooling and overclock it.
http://www.pcper.com/reviews/Processors/Intel-Core-i7-6700K-...