Ill run this when I get home. But for those of you getting low GPU to CPU speed, have you tried turning on/off the optimizations in bios to change the way htt sends information? They might do something to bandwidth. These are the options:
VC1 Traffic
Isochronous Flow Control Mode
UnitID Clumping 2/3 & B/C
2x LCLK
HT Link Tristate (disable should increase performance)
VC1:
This BIOS feature allows you to manually map a specific traffic class to the second (VC1) virtual channel of the PCI Express graphics port. This is the higher-priority virtual channel, so mapping a specific traffic class to it will increase bandwidth allocation priority for that traffic class. However, this is not a requirement
Isochronous Flow-Control Mode: This has to do with how information is passed between the CPU, the GPU and the RAM along the NorthBridge. It has been a part of the BIOS for HT since AGP 8X, but the option to enable or disable it is a fairly recent addition. When this option is enabled, it assigns the information a number, in the order it was received. Each bit of information is then processed in that order along the route. In toher words, there is no loss of information, but the processing in this orderly manner has drawbacks. If you choose to enable this feature, you will also need to enable UnitID Clumping and then under PCI-E COnfiguraiton and the NB-SB section of the BIOS, VC1 needs to be enabled as well.
UnitID Clumping: Simply put, it accounts for not all devices being equally quick at processing information. This allows each device to support a longer waiting line. VC1 accounts for a major drawback of Isochronous Flow-Control mode in that the flow control mode does not allow any information to break line. Everything must wait it's turn. Therefore, if one piece of info is intended for the CPU and in front of it is info the for GPU, the info for the GPU needs to be processed before the CPU info is processed; plus, if there is a waiting line of info to be processed onthe GPU, the CPU info is held up all that much longer. VC1 comes to the rescue by letting the CPU info break line, bypassing the GPU info jam to join the CPU info queue.
2xLCLK: This setting only affects HT 3.0, so Phenom's may benefit from it while with Athlon's, it just does not apply. LCLK stands for Latency Clock. The 2x means that instead of one full bandwidth HT Link you are requesting two half bandwidth HT Links. For performance, at times it is better to have a two lane highway; traffic flowing in both directions at the same time along the same strip of asphalt at 50mph, than it is to have a single lane highway along the same strip of asphalt with traffic lights controlling the directional flow at 100mph.
Tristating is a power saving feature in addition to ASPM linking. Whatever sections you want to enable Tristate in, you reduce the energy needed to run that area, but the downside is that you also reduce that area's performance
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