As it turns out, and as we already suspected, not all of the Haswell-E CPUs will have the same number of PCI-Express lanes. Both the Core i7-5960X and the Core i7-5930K will be able to address 40 PCI-Express lanes, but the cheapest Core i7-5820K will only have access to 28 lanes. TechPowerUp forum member "623" has seemingly confirmed this through leaked manuals of Gigabyte's X99 motherboards.
|CPU||Cores/Threads||Frequency||L3 Cache||PCI-Express Lanes||TDP||Expected Price|
|i7-5820K||6 / 12||3.3 GHz||12 MB||28||140 W||$400|
|i7-5930K||6 / 12||3.5 GHz||15 MB||40||140 W||$600|
|i7-5960X||8 / 16||3.0 GHz||20 MB||40||140 W||$1000+|
Of course, this shouldn't come as too much of a surprise. Being able to grab a 6-core Haswell-E processor for the rumored price of $400 makes for a good deal, and there must be a concession made somewhere. While the Core i7-5960X and the Core i7-5930K will be able to address triple-GPU configurations with 16-16-8 lanes, the Core i7-5820K will only manage a 16-8-4 configuration, at best. This leaves the third GPU quite choked, and if you have any additional PCI-Express devices operating over lanes that are wired directly to the CPU, you will run into even more issues. We would have hoped that the i7-5820K would be able to address the slots in an 8-8-8 configuration; however, the manuals posted make no mention of such a configuration. Dual-GPU configurations won't present a problem, but for anything more than that you're going to want a Core i7-5930K or above.
Of course, you can't really ding Intel for doing this. The company will be offering a 6-core chip for hopefully under $400, and if you're interested in a multi-GPU setup that needs the extra PCI-Express lanes, you can probably afford the extra $200 for the upgrade to the Core i7-5930K anyway. Thus, if you're already playing around with the thought of acquiring a Haswell-E system with three or more GPUs, you'd better start adjusting your wishes or your budget.
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No, cause you just spent all your money on a triple GPU setup ^^
All the other sources I read say that it has 15MB L3
And should games start being ported with greater CPU requirements from consoles threading, having 6 actual cores with 12 threads available should really help. I'm just not sure I'm sold on the DDR4... great speeds and bandwidth, but horrible timings. Might be able to be overclocked though... maybe... Will this CPU support quad channel memory like the 4930?
They are just splitting hair in four here....
It's not about mutli GPU setups, some might need to install some other PCIe cards and when that is installed, does your PCIe lanes for your GPU still get reduced down to say from x16 to x8?