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question about how to read CPU-Z

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dito

Member
Joined
May 28, 2009
Location
Vacaville, CA
I'm relatively new to overclocking. I've upped the CPU speed a little, from 333 to 355(x8.5, Q9550). My question is actually about how to read the memory portion of CPU-z. I have 4 sticks of Corsair Dominator Dual Channel 2048MB PC8500 DDR2 1066MHz Memory. It's rated at 1066mhz, but I get this in CPU-Z
cpu-z1.jpg

cpu-z2.jpg

as you can see, it says dram running at 355mhz, with a fsb to dram ratio of 1:1. why is the max bandwith pc2-6400 (400mhz). am i missing something? should i be setting the dram frequency to something else? thanks in advance!
 
You can disregard the Max Bandwidth - PC2-6400 result under the SPD tab in CPU-Z. The SPD is programmed at: JEDEC standard 5-5-5-15 values at 800 MHz (PC2-6400). So going by the screenshots you posted, the RAM is currently running at 710 MHz (355 MHz x 2) at a 1:1 FSB : DRAM ratio (333/667 NB strap). At the current FSB of 355 MHz, you need to change the strap to 266/800 (a 2:3 ratio) to end up with an effective 1065 MHz DRAM frequency (shown as 532.5 MHz in the DRAM Frequency field of CPU-Z). If you haven't already, manually change (take off AUTO) the four primary RAM timings to CL 5-5-5-15 (CAS-tRCD-tRP-tRAS), leave all sub-timings on AUTO for the time being, and change the Vdimm to 2.1v
 
changed the bus speed up to 363 from 355, after i was able to get 5:6 FSB : RAM ratio. It seems my mobo (TP43D2-A7) really sucks at memory overclocking, only giving me 4 options at 363mhz :auto, 726mhz, 871mhz or 1161mhz. 1161 won't boot, 871 does fine but it's only at 871mhz, instead of 1066mhz. I guess that's as close as I'm going to get with this mobo, sucks! at least i was able to up the FSB a little, well will run some prime 95 now...thanks for the help!
 
If the PC qon't boot at a DRAM frequency of 1161 MHz (333/1066 NB strap; 5:8 ratio), then the problem is more than likely with one or more voltages. Post all your current voltage settings (VTT, vNB, Vdimm, PLL, etc.) at an FSB of 355 MHz and 5:8 (or the highest FSB / DRAM frequency that POST's and is stable). If any voltages are set to AUTO then use a program like Biostar's T-Utility, or the Hardware Monitor section of the BIOS to read them.
 
First off, THANK YOU redduc900 (BTW I am a motorsports photographer, mainly motorcycles in northern california, gotbluemilk.com)I hav ebeen trying to read, reread about overclocking and some it goes in, but just doesn't compute. THANKS for helping out a NOOB!

Here's a screenshot of the voltages, I took off auto on the 4 main timings, already had correct timing/voltage (5-5-5-15 @ 2.1v). also took off auto on anything else I could control, FSB frequency set to 1333, dram frequency currently set to 871, PCI Express Frequency set to 100, memory voltage set to 2.1v. the only thing i wanted to change i couldn't was cpu voltage. i only had 4 options again:auto, +5%, +10%, and +15%.
oc1.jpg
 
i actually tried cpu +5% and it still wouldn't boot to windows, so i reverted back to 871mhz instead of 1161mhz.
 
that's what i thought too. here may be a stupid question, does the video card have any relation to how much you can overclock the cpu? i only have a 512mb EVGA 9500 GT...?
 
No , you video card will not in any way impact your cpu overclock .

One question tho , what power supply are you running ? wattage and all.
 
lol 450 is you wattage . dont worry tho :) was just making sure you are set in that department , yeah just raise you fsb further and raise/lower the ratios do adjust to you desired clock , also when u get instability you might want to bump up the cpu voltage , but do that only with aftermarket heat sink .
 
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