Tapeless workflows and Sandy Bridge or other PC's: KISS or LOVE? at DVinfo.net

Harm Millaard · January 18th, 2011, 11:00 AM

For those interested in the new Sandy Bridge architecture, this may be worth reading. At least I did my best to make this readable and informative for you.

Adobe Forums: Tapeless workflows and Sandy Bridge or...

Randall Leong · January 18th, 2011, 01:05 PM

Thanks for the proof that the LGA 1155 platform is ill-suited for anything more than a KISS drive configuration. Although there are technically four PCIe lanes open for PCIe expansion cards on the LGA 1155 platform (after accounting for onboard USB3, PCIe-to-PCI bridge and additional SATA/IDE controllers), the few motherboards that have PCIe x4 slots actually share the bandwidth of that slot with the PCIe x1 slots on those same boards. This means that ANY card plugged into a PCIe x1 slot would have forced the x4 slot to run in x1 mode. That hurts the performance of most discrete hardware RAID controllers. The only other place to put a RAID card would have been the second PCIe "x16" graphics slot (which is bifurcated from the main PCIe x16 slot, and thus both slots would have been forced to run in x8 mode). This does hurt MPE GPU performance.

A few high-end LGA 1155 motherboards have onboard PCIe lane repeaters. Unfortunately, while they create additional PCIe lanes, they do not change the total bandwidth of the CPU's integrated PCIe controller. So instead of 16 PCIe lanes operating at full PCIe 2.0 bandwidth, you now have 32 PCIe lanes that are artificially restricted to PCIe 1.0 bandwidth -- 2.5 GT/s instead of 5.0 GT/s.

Randall Leong · January 18th, 2011, 09:28 PM

The condensed version of my above post is:

Unless someone has only an Nvidia graphics card and a discrete hardware RAID card (and no other expansion cards whatsoever), the current Sandy Bridge (LGA 1155) platforms do not allow both the graphics card and the RAID card to be run at their full speeds at the same time. Either the disk performance or the GPU performance would suffer, especially if that configuration also includes a sound card that's of better quality than the onboard one.

January 18th, 2011, 11:00 AM	#1
Harm Millaard Trustee Join Date: Aug 2006 Location: Rotterdam, Netherlands Posts: 1,832	Tapeless workflows and Sandy Bridge or other PC's: KISS or LOVE? For those interested in the new Sandy Bridge architecture, this may be worth reading. At least I did my best to make this readable and informative for you. Adobe Forums: Tapeless workflows and Sandy Bridge or...

January 18th, 2011, 01:05 PM	#2
Randall Leong Major Player Join Date: Nov 2009 Location: Melrose Park, Illinois, USA Posts: 936	Thanks for the proof that the LGA 1155 platform is ill-suited for anything more than a KISS drive configuration. Although there are technically four PCIe lanes open for PCIe expansion cards on the LGA 1155 platform (after accounting for onboard USB3, PCIe-to-PCI bridge and additional SATA/IDE controllers), the few motherboards that have PCIe x4 slots actually share the bandwidth of that slot with the PCIe x1 slots on those same boards. This means that ANY card plugged into a PCIe x1 slot would have forced the x4 slot to run in x1 mode. That hurts the performance of most discrete hardware RAID controllers. The only other place to put a RAID card would have been the second PCIe "x16" graphics slot (which is bifurcated from the main PCIe x16 slot, and thus both slots would have been forced to run in x8 mode). This does hurt MPE GPU performance. A few high-end LGA 1155 motherboards have onboard PCIe lane repeaters. Unfortunately, while they create additional PCIe lanes, they do not change the total bandwidth of the CPU's integrated PCIe controller. So instead of 16 PCIe lanes operating at full PCIe 2.0 bandwidth, you now have 32 PCIe lanes that are artificially restricted to PCIe 1.0 bandwidth -- 2.5 GT/s instead of 5.0 GT/s. Last edited by Randall Leong; January 18th, 2011 at 10:19 PM.

January 18th, 2011, 09:28 PM	#3
Randall Leong Major Player Join Date: Nov 2009 Location: Melrose Park, Illinois, USA Posts: 936	The condensed version of my above post is: Unless someone has only an Nvidia graphics card and a discrete hardware RAID card (and no other expansion cards whatsoever), the current Sandy Bridge (LGA 1155) platforms do not allow both the graphics card and the RAID card to be run at their full speeds at the same time. Either the disk performance or the GPU performance would suffer, especially if that configuration also includes a sound card that's of better quality than the onboard one.