Clarification on BIOS Options: LDT Frequency & SPP<->MCP Ref Clock MHz

desolator4u

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Mar 3, 2011
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Sup ppl?
I have searched all over the net, yet I just cannot find anything with a good clarification as to what the hell SPP<->MCP Ref Clock, Mhz and LDT Frequency: 5x are for.

SPP<->MCP Ref Clock, Mhz ususally has Auto, 100 or 200 but I don't know what it is suppose to affect. I can tell it has to do with the Southbridge from MCP and SPP, well I have no idea what that is; Standard Parallel Port maybe?
And for LDT Frequency, it usually has 5x from what i've seen online from people's BIOS settings. I think I once came across something that said it is related to the FSB speed.

If this is only specific to older MoBo's and Chipsets, like the 680i that i'm using in my Striker Extreme, that hardly anyone uses anymore, then I apologize, but i'd really like to finally clear up my confusion as to what these two options are for.

Thanks
~Des