It could be because core to core ping times are rather slow. Moving from Ring to Mesh seems to be causing problem especially in games. In Ryzen's case we learned that when certain threads were running on different CCX, there was very clear penalty for peformance. Atleast in Zen's case latency within one CCX was reasonably low for threads which has a lot of communication in between.
Unfortunately in the case of 7900x, there ain't a single core-pair with low latency.
https://www.pcper.com/reviews/Proce...X-Processor-Review/Thread-Thread-Latency-and-
The idea here is that while it is worse on LCC, it scales way better than ring bus with core count.If it is this bad with the LCC die, I suspect it will be worse on the HCC and XCC dies.
Also, latency is higher, but so is bandwidth.
It just occurred to me how absurdly bad the value of the i7-7740X is.
The i7-7740X retails for $349.99. The i7-7800X is $389.99. Seems like you'd be a fool to not throw down the extra $40.
Because part of the $100 goes to Intel. Gotta get ST performance chasers (gamers) who demand the best to go X299 if they want the extra few hundred MHz over their 7700k build. Then they buy a new board again for Coffee Lake.
I don't think many will do that. But who knows...
Edit: Real answer may that by taking out iGPU and having the physically socket bigger helps keep it cool and OC better. KBL-X on Z270 would only have 1 of those advantages.
Have they though? It seems to me they just disabled it.
The die is identical to the one on KBL-S, the iGPU is just disabled. The changes are in the packaging (LGA 2066 package) as well as obviously the much more robust power delivery systems of your average X299 board vs your average, much cheaper LGA 1151 board.
Because part of the $100 goes to Intel. Gotta get ST performance chasers (gamers) who demand the best to go X299 if they want the extra few hundred MHz over their 7700k build. Then they buy a new board again for Coffee Lake.
I don't think many will do that. But who knows...
Edit: Real answer may that by taking out iGPU and having the physically socket bigger helps keep it cool and OC better. KBL-X on Z270 would only have 1 of those advantages.
Would it really give you much over a 7700K though?The i7-7740X would be so much better if it could be used with Z270 motherboards instead of X299. Why pay $100+ dollars extra for features you can't use ?
Would it really give you much over a 7700K though?
Coffee Lake-X will work in X299 boards
Coffee Lake-X is launching simultaneously with Coffee Lake? If not, ST performance chasers wouldn't wait.
They could have done that long ago. None of us wanted the IGP anyway.If it were available for LGA 1151, it would literally be an i7-7700K.
I would say broadwell E is the worst HEDT launch. No performance increase at all due to minimal ipc gain and poor overclocking. The performance is improved in most cases with Skylake X, but thermals and power usage need to be improved. Perhaps power usage and performance, especially in gaming, will improve as bioses mature. I am however mystified by the decision to use TIM. It is a disappointment to loyal intel users, and of course like throwing raw meat into a school of sharks to the crowd looking for any excuse to bash intel.I think we were expecting Skylake with more cores, that's what it is but not really, the changes to cache and the mesh arrangement seem to have a negative impact on significant cases, maybe gaming is another victim of it, but it seems Intel implies is more related to power management!?
another thing with Skylake that we would expect was good power usage, well, it's not here... combined with the TIM thing, it feels like the high clocks are a late reaction to competition!? or is it just inevitable because of the changes (cache, mesh...)?
still performance is there it's very strong most of the time, and if you are willing to invest on a really good cooler and delid (RIP warranty) it can OC quite far.. but it makes you wonder about the 18 core chip, is that thing going to be like the Xeons, 2.4GHz base clock or something?
also the high risk of killing the CPU when switching from Skylake to Kabylake is...
but 10 core drop in price from the 6950X looks good, even the 7800x looks like a good competitor to the Ryzen R7 (even 1700 OC), the problem is that when you factor the cost of motherboards, high end cooling, possible delid and so on not really, but if you are going for high end MB+cooler anyway the 7800x OC is probably the better choice
still, this is probably the worst Intel "HEDT" launch ever.
The issue was the fact that you had to add a second ring and buffer between them. That increased latency well over twofold. Now the highest latency on XCC won't go higher than ~160% of highest LCC one if my napkin math is correct.Was is more so bandwidth that was the problem with the ring bus setup as core counts increased?