F2-8500CL5D-4GBPK on DFI LANParty 790FX UT M2R

[gordan]

What timings should be used on this motherboard with a quad-core Phenom 9950?
"auto" with speed manually set to DDR2-1066 and RAM voltage manually set to 2.10V is unstable. Do timings need to be tweaked/relaxed/changed slightly for the Phenom? If so, what to?

Thanks.

[G.SKILL]

you'll need to add the northbridge voltage to 1.4-1.5v
and you can set timing to 5-5-5-15 manually or just keep it auto, it's almost the same
thanks


G.S

[gordan]

Thanks for that. I'll look into the NB voltage. But isn't the MCH built into the CPU? If so, the NB voltage won't affect the memory stability, will it? And is the NB voltage bump required even with just 2x2GB DIMMs, as per the kit part number listed?

The "auto" timings get set to 5-7-7-20. My concern, however, is that EPP lists tRC=48, tWR=13 and the maximum the motherboard allows is tRC=41, tWR=8. And "auto" settings are lower than the maximum settable.

Finally, "auto" tRFC is about 127ns (IIRC). I seem to remember seeing something about this needing to be increased to 195ns. Is there any truth in that? What should tRFC be set to for this memory? I couldn't find any relevant entries in the SPD/EPP dump.

Note that when I say that the setup is unstable, it errors out after 2-12 hours. It would pass a cursory stability test, but not a proper stability test for 24/7 operation for full load for months at a time (I don't consider a system "stable" if it can't handle 100% load on all components permanently - my testing is usually for a week before deploying.

Anyway, I'll try the NB voltage as you suggested.

Just out of interest - if I were to run 4x2GB with two of the kits in question, what timings/voltages/settings would I need to run?

Many thanks.

[G.SKILL]

in theory, there is no need to add northbridge voltage since memory controller is built in CPU
but actually, we still have to add northbridge voltage in BIOS to run DDR2 1066, or sometimes it won't boot
if the timing is not correct, then please set it to 5-5-5-15(tCL-tRCD-tRP-tRAS) 2T manually and keep others sub timing auto

and it seemed 4 sticks of dual channel DDR2 1066 is not supported for AMD platform yet
thanks


G.S

[gordan]

Thanks for that. The motherboard won't allow setting tRAS to less than 16, so I'm currently testing 5-5-5-16 @ 2T with CPU NB bumped up to 1.40V (what's the default? 1.30V?). It's the longest it's lasted testing so far at 13 hours and still going. Hopefully it'll stay that way.

Thanks for your help.

[G.SKILL]

that's fine
tRAS is the number of clock cycles taken between a bank active command and issuing the precharge command
it would not affect performance much
and hope the problem is solved


G.S

[gordan]

and it seemed 4 sticks of dual channel DDR2 1066 is not supported for AMD platform yet

It may be unsupported, but it works just fine. 4x 2GB just passed 2 days of OCCT, same settings as 2x 2GB (5-5-5-16-2T@1066), with 1.40V CPU NB.

[G.SKILL]

fine
thanks for the info


G.S