Will Intel not make a CPU for the X79 motherboards that enables 3.0?

[funpilot]

Posted this question on the main motherboard forum, but wanted to ask here if that is the case is there anything innovative that ASRock can do in their future bios to get around that if that actually happens? I have the x79 Extreme9 unopened and am wondering if I should RMA it quickly and go to the Z77 series?

This question comes from a thread posted on nVidia suggesting Intel is backing off creating a CPU for X79 that will support 3.0.

 

[funpilot]

This Intel link shows NO PCI-e 3.0 capability.

http://www.intel.com/content/www/us/en/chipsets/performance-chipsets/x79-express-chipset.html

 

[jaquith]

Currently, this problem is on nVidia GTX 600 series GPUs, and there's no concrete information other than what's posted below. TH is in the process of working on an article. This is a current validation issue with the SB-E CPU's and while the PCIe 3.0 support is on the SB-E nVidia called into question PCIe 3.0 support on the SB-E.

I truly wish I could give you better information, but this is all I have useful or not.

Here's a very good link -> http://rog.asus.com/forum/showthread.php?11900-GeForce-GTX-680-Release-Driver-Limits-PCI-Express-to-Gen-2.0-on-X79-SNB-E-Systems

The SB-E has 40 primary PCIe lanes, 32 lanes of PCIe 3.0 are dedicated to the GPU(s), 8 lanes of PCIe 2.0 for chipset, all LGA 2011 CPUs & MOBO's are capable of PCIe 3.0, some BIOS upgrades have addressed PCIe 3.0 issues. Ditto the Z77 has the same 8 lanes of PCIe 2.0. All LGA 1155 including the IB have half the number of PCIe lanes to the GPU in comparison to LGA 2011; SB/LGA 1155 16 lanes of PCIe 2.0, IB/LGA 1155 16 lanes of PCIe 3.0 vs SB-E/IB-E/LGA 2011 32 lanes of PCIe 3.0 (subject to validations) to the GPUs then split in various ways.

Before with LGA 1156 e.g. P55 and LGA 1366 e.g. X58 the GPU(s) ran through the Chipset, but since Sandy Bridge LGA 1155 and Sandy Bridge Extreme LGA 2011 all GPU lanes are a direct path to the CPU to reduce 'latency.' Apparently, the 'issues' are limited to the LGA 2011 MOBO's (BIOS Fix) and current SB-E CPUs.

Therefore, the SB-E running e.g. GTX 600 series or HD 7000 series GPU(s) is PCIe 3.0 clean *IF the drivers allow it. The problem is with nVidia, the SB-E & AMD HD 7000 series runs PCIe 3.0 just fine. Yes, I've seen this -> http://www.geforce.com/hardware/desktop-gpus/geforce-gtx-680/specifications
*GeForce GTX 680 supports PCI Express 3.0. The Intel X79/SNB-E PCI Express 2.0 platform is only currently supported up to 5GT/s (PCIE 2.0) bus speeds even though some motherboard manufacturers have enabled higher 8GT/s speeds.

Registry fix (hack) to force the GTX 680 to run in PCIe 3.0 mode; see - http://tinyurl.com/7awc9lv (RMPcieLinkSpeed, DWORD = 0004, etc. IMO - It's a bad act by nVidia...to Disable, if this is an issue on some LGA 2011 then the driver installer 'should' detect and notify the end user to rectify vs all LGA 2011 suffer from the few LGA 2011 with a BIOS issue.

Problem this might be ditto with the IB but Idon't know sine the IB CPU's aren't available nor any testing, since there's no difference in the PCIe 3.0 spec on either the SB-E or IB.

The HD 7000 series does run in PCIe 3.0 mode on LGA 2011.

You may also want to read - http://www.techpowerup.com/162942/GeForce-GTX-680-Release-Driver-Limits-PCI-Express-to-Gen-2.0-on-X79-SNB-E-Systems.html
GeForce GTX 680 supports PCI Express 3.0. It operates properly within the SIG PCI Express Specification and has been validated on multiple upcoming PCI Express 3.0 platforms. Some motherboard manufacturers have released updated SBIOS to enable the Intel X79/SNB-E PCI Express 2.0 platform to run at up to 8GT/s bus speeds. NVIDIA is currently working to validate X79/SNB-E with GTX 680 at these speeds with the goal of enabling 8GT/s via a future software update. Until this validation is complete, the GTX 680 will operate at PCIE 2.0 speeds on X79/SNB-E-based motherboards with the latest web drivers.

Ivy Bridge and Z77 Chipset (Panther Point):

HD 7900 Series running PCIe 3.0 on SB-E:

GTX 600 Series running PCIe 3.0 on SB-E (fix applied):

 

[funpilot]

Thank you for your reply. Hope others will jump in as well. So, I should have no issues staying with my ASRock X79 with a I7-3820 CPU per se, my issues are with the nVidia bios at this time then?

 

[jaquith]

The issues:
1. Most LGA 2011 have some sort of BIOS PCIe 3.0 update, requiring an update:
X79 Extreme9 (BIOS version 2.0 is the latest, but no ref to PCIe 3.0 update) - http://www.asrock.com/mb/download.asp?Model=X79%20Extreme9&o=BIOS
2. nVidia must validate PCIe 3.0 on SB-E. To date it's limited to PCIe 2.0:
"*GeForce GTX 680 supports PCI Express 3.0. The Intel X79/SNB-E PCI Express 2.0 platform is only currently supported up to 5GT/s (PCIE 2.0) bus speeds even though some motherboard manufacturers have enabled higher 8GT/s speeds."

The hack may or may not work...

Frankly, PCIe 2.0 vs PCIe 3.0 on today's GPU's does zip *, and with 2-WAY PCIe 2.0 x16/x16 on LGA 2011 is the same bandwidth as 2-WAY PCIe 3.0 x8/x8 on IB + LGA 1155 with GEN3 or Z77's. PCIe 3.0 becomes relevant once 4K Monitors became available to the 'Consumer' and in mass production, but by then it's going to be time to upgrade your PC & GPU(s).

PCIe 3.0 vs 2.0 - http://www.hardwarecanucks.com/forum/hardware-canucks-reviews/49646-amd-radeon-hd-7970-3gb-review-21.html
* EXTREME PCIe 3.0 vs 2.0 - http://www.evga.com/forums/tm.aspx?m=1537816&mpage=1&print=true

 

[funpilot]

Looks like someone from Intel posted a response to my similar questions out on the Newegg forum. We must all realize inspite of his wording, it is only his opinion, but a nice one at that.

http://www.eggxpert.com/forums/thread/814030.aspx

 

[jaquith]

Pfff...I know Chris, I know more.

 

[funpilot]

Anyone from ASRock want to comment on when a bios upgrade will specifically focus on pci-e 3.0 ?

 

[jaquith]

ASRock, ASUS, MSI, you name it will never reply to a forum post here. Once in a Blue Moon you'll see the Corsair, G.SKILL and once I've seen TigerDirect post here.

Again, the problem isn't the MOBO or the Chipset, the problem is validation of the SB-E CPU & nVidia GTX 600 series GPU(s) - period. Any ASUS and most others follow suite on their X79 BIOS settings to allow either PCIe 3.0 (default) or PCIe 2.0 manually. Therefore, ASRock, ASUS, MSI, you name it will simply state e.g. "their X79 MOBO support PCIe 3.0 and please make sure you have the latest BIOS to insure proper support...and to take it up with Intel & nVidia."

The original LGA 2011 SB-E CPU spec from Intel 'had listed' PCIe 3.0 support to the 32-lanes dedicated to the GPU lanes, and all 2nd & 3rd gen CPU's SB/SB-E/IB are all 8 lanes of PCIe 2.0 to the chipset.

IB - I can only speculate based upon time (Testing Time aka Validation) availability for both the IB and nVidia GTX 600 series that the IB is 'should be' validated PCIe 3.0 for nVidia. AMD is less restrictive i.e. less controlling than nVidia. nVidia requires a minimum of PCIe 2.0 x8 per GPU to provide it's 'BIOS Key' (licensing) to the MOBO Mfg for SLI, whereas AMD allows open (free) access therefore if the GPU 'fits', per their CF Chart, and up to 4 GPU cores then presto you can have CF on even PCIe 2.0 x4 lanes if you choose.