INTEL CORE I5-7600K REVIEW
https://iamg4mer.blogspot.com/2017/01/intel-core-i5-7600k-review.html
Kaby Lake processors, aka 7th Generation Core, are Intel's new hotness, with plenty of marketing muscle to back them up. Are the new parts a must-have upgrade, though? The simple answer is no, particularly when it comes to desktop users. As the 'Optimization' phase of Intel's Process-Architecture-Optimization paradigm, we didn't expect otherwise. Kaby Lake uses a refined 14nm process to improve clock speeds without noticeably altering the power requirements of Skylake, and gets a few additions (HEVC 4K decode/encode support) that will mostly benefit mobile users.
ADDITIONAL READING
Our main Kaby Lake hub includes additional charts comparing stock performance, plus additional architectural details. Our Kaby Lake overclocking article does the same for all tested CPUs at overclocked settings.
The Core i5-7600K is mostly a lateral move for the Core i5 series of processors, with a slight upward trend in performance—exactly the same approach Intel has taken since the Core i5-2500K. There's also a new platform that increases the number of PCH chipset lanes to 24, but raw performance should scale directly in proportion to clock speed. Compared to the i5-6600K, clock speed on the i5-7600K is eight percent higher (give or take half a percent).
The good news is that, at least in markets where the i5-7600K is readily available, it effectively replaces the i5-6600K at the same price. And make no mistake, the i5-7600K is a better (ie, faster) processor than the i5-6600K—it's just not a revolution in CPU performance. If you upgraded to a Core i5/i7 desktop part from the Haswell / 4th Gen Core period or later, you can sit out this round, and if you're primarily worried about gaming performance, that advice applies even more.
Compared with other processors, the i5-7600K may place below the midpoint of many of the charts, but that's largely because the charts include a collection of high-end parts. For lighter work, the difference between most of the Intel parts is negligible. If you're mostly doing office work, surfing the Internet, and playing games, Core i5 is the sweet spot in bang for the buck.
KABY LAKE TESTBED
The other way of looking at the CPU performance charts is that if you aredoing CPU intensive work, like video editing, there's definitely a benefit in moving to Core i7 over Core i5, and potentially even greater gains if you move to the X99 platform. For workloads that scale well with core count, even running at stock clocks the Haswell-E and Broadwell-E parts are potent. The Core i7-7700K is typically 40-50 percent faster than the i5-7600K in CPU heavy work, and the i7-6900K is sometimes more than twice as fast.
Overclocking helps some, but the 7600K sample I tested wasn't quite stable at 5.0GHz and I had to drop to 4.9GHz. I've seen other reports of 5.0 to 5.2GHz, but bear in mind that overclocking is never guaranteed. I suspect my sample is about as low as i5-7600K will reach with liquid cooling, and if you're adventurous enough to delid and use a higher quality TIM (Thermal Interface Material), you should be able to drop temperatures and eke out another 100-200MHz. But even with overclocking, the 7600K can't quite catch the i7-6700K or i7-7700K.
Compared to the previous generation, the i5-7600K is eight percent faster than the i5-6600K, exactly the difference in clock speed. But what about older CPUs like the i5-4670K, i5-3570K, and i5-2500K? I don't have full test results so instead I researched the question. i5-7600K is ~8 percent faster than i5-6600K, which is ~12 percent faster than i5-4670K; the 4670K is ~9 percent faster than i5-3570K, which is ~8 percent faster than i5-2500K. That's in CPU intensive (non-gaming) workloads, so combined the Kaby Lake i5-7600K is a bit more than 40 percent faster than an old i5-2500K—assuming all chips are running stock; overclocking would narrow the gap slightly.
Gaming on the i5-7600K
I ran some benchmarks showing gaming performance on Kaby Lake, and while those results use the i7-7700K, dropping down to the i5-7600K doesn't make any significant difference. I won't repeat the charts here, but the HD Graphics 630 is the bottleneck when it comes to gaming performance. Gamers will definitely want a discrete graphics card.
If the difference in raw CPU performance isn't particularly noteworthy, the gaming potential of the i5-7600K is even less so. It's not that CPU performance doesn't matter for games, but it's a far less important aspect than graphics performance. Even with a GTX 1080, most of the fastest CPUs are within a few percent of each other on the CPUs I tested.
Overall, the i5-7600K is less than one percent faster than the i5-6600K in games. Overclocking improves average gaming performance by another 1.6 percent over stock, but anything less than five percent is practically meaningless. More importantly, everything from the i5-6600K through the i7-7700K is effectively tied for gaming potential using one of the fastest graphics cards available.
There are slightly more noticeable individual differences in games, of course. Ashes of the Singularity, Civilization VI, and Hitman all show more than a 10 percent improvement in performance going from a 6600K to a 7600K. But with fourteen demanding games tested, more than half show less than a one percent change in performance. It's why we routinely point to the Core i5 unlocked CPUs as the best overall gaming processors—they're 97 percent of the performance of the Core i7 offerings, at two thirds the cost.
As above, I also researched gaming performance with the various Core i5 processors dating back to the i5-2500K. There's a wider margin of error, but on average the i5-7600K is ~1 percent faster than i5-6600K. That chip is ~5 percent faster than the i5-4670K, which is ~4 percent faster than i5-3570K, and IVB is ~4 percent faster than i5-2500K. Combined, i5-7600K is about 15 percent faster for gaming than the i5-2500K.
Much of this depends on the games tested and the GPU used, so there are instances where the gap is smaller or larger, but the difference in gaming performance shouldn't be greater than the CPU gap (around 30 percent, see above). Ivy Bridge and Sandy Bridge are becoming a potential bottleneck in games, particularly with high-end GPUs like the GTX 1070/1080, but if you're running more modest hardware like a GTX 970 or R9 390, the performance loss will typically be less than 10 percent.
