Questions about a Alienware Aurora r4 ALX

Hi saucefar,

The Alienware Aurora R4 ALX computer comes with PCI express 2.0 as you mentioned.

The main difference between 2.0 and 3.0 is the bandwidth available to the cards, thus allowing greater amounts of data to be transferred to them. The potential for increased data throughout and performance within an embedded computing system is the primary application difference between the PCI Express 3.0 and 2.0 and interfaces.

Base Clock Speed:  PCIe 3.0 = 8.0GHz, PCIe 2.0 = 5.0GHz

Data Rate: PCIe 3.0 = 1000MB/s, PCIe 2.0 = 500MB/s

Total BandPCIe 3.0 = 32GB/s, PCIe 2.0 = 16GB/s

Data Transfer Rate: PCIe 3.0 = 8.0GT/s, PCIe 2.0= 5.0GT/s

PCIe 3.0 features a number of interface architecture improvements, but communicates at the same interface speeds used in PCIe 2.0. PCIe 3.0 achieves twice the communication speeds of PCIe 2.0 through various architecture and protocol management improvements.

In simple terms PCI express 3.0 and 2.0 are pretty much the same but the former has an increased speed and performance.

Dear saucefar,

GPU-Z is not always able to detect the PCIe 3.0 feature. When I read your question, I suddenly entered my Aurora R4 Bios at the system startup by pressing F2. Then, I went to Advanced < Integrated Devices < PCIe Gen3 < Enabled. So, to answer your question, the Aurora R4 motherboard supports PCIe 3.0. You can enable or disable it by entering the Bios. I have a GTX 680 SLI. Hope my answer can help you.

Hashley,   More great info. Thanks for taking the time to post it.   So Dell's implementation of x79 does provide at least enough PCIe lanes to full-bandwidth support one video card at PCIe x16 v3.0. Those screen-shots are golden.   What's confusing to me is the official Intel block diagrams (see above post) show only PCIe v2.0 ... your thoughts?

Tesla1856,

the answer lies in the motherboard model. The official Intel block diagrams for the upcoming X79 mobos date back mid 2011 and set a landmark for future motherboard manufacturers, establishing ''standard'' PCIe 2.0 and USB 2.0 solutions. After Intel announcement, many motherboard manufacturers decided to modify the ''standard'' scheme recommended by Intel and different motherboard models appeared mixing PCIe 2.0 and/or PCIe 3.0, together with USB 2.0 and/or 3.0. Moreover, Intel original scheme for X79 mobos was originally limited to PCIe x8 (http://ark.intel.com/products/64015/Intel-BD82X79-PCH#infosectiongraphicsspecifications) while most manufacturers decided to extend it to PCIe x16 just after Q3 2011. So, the original Intel scheme is not representative of the real situation arising right after.

The ultimate Alienware Aurora R4 X79 mobo is based on the MSI X79MA-GD45 motherboard model. If we read the specs here http://us.msi.com/product/mb/X79MA-GD45.html#/?div=Overview they are just identical to those Alienware indicated for its Aurora R4 here http://www.dell.com/us/p/alienware-aurora-r4/pd.aspx?~ck=mn : both have 2x PCIe x16 + 2x PCIe x1; both have 6x USB 2.0 ports + 2x USB 3.0 ports; both have 4x DDR3 memory slots; both have unified UEFI; and obviously both have PCIe 3.0 on board.

Three conditions must be fulfilled at the same time to have a fully working PCIe 3.0: the CPU, the GPU, and the motherboard.  The first must be an Ivy Bridge or a Sandy Bridge E; the second must be a Geforce 600 series or a Radeon 7000 series; the third must be a Z77 mobo or X79 mobo as ''revised'' by many manufacturers after Intel original announcement. If one of those three requirements is missing there will be no fully working PCIe 3.0.

Those problems don't concern the ultimate Aurora R4 version because: 1) it comes with Sandy Bridge E CPUs, i.e. i7 3820, 3930k, 3960x, all native PCIe 3.0 compliant CPU. Previous Ivy Bridge CPUs had to come with a PCIe 3.0 controller instead, and this was no common rule because IB were PCIe 2.0 native.; 2) it comes with Geforce 600 series or Radeon 7000 series, both PCIe 3.0 native; 3) it comes with a MSI X79MA-GD45 mobo model, formally rebranded as ''Alienware'' motherboard, and both are PCIe 3.0 native.

I have also tested the Bus Interface readout using GPU-Z after applying the Nvidia fix 3.0 and it seems that the Alienware X79 mobo can handle full-bandwidth support for two video cards at PCIe x16 3.0. The ''Render Test'' that I have recorded and uploaded here http://www39.zippyshare.com/v/99200174/file.html shows that the Alienware X79 mobo has enough power to fuel a SLI config x16 3.0. Both my GTX 680 SLI worked @ x16 PCIe 3.0 during the test (see the bottom-left side inscriptions during the red background render test).

In a nutshell, the official Intel block diagrams are a mere 'standard' that has been later revised by many motherboard manufacturers adding the PCI 3.0 and other important features. The truth lies in the mobo model, case by case. And the ultimate Alienware Aurora R4 motherboard comes with all three requirements ensuring full PCIe 3.0 support.