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Asus P5Q-E FSB:DRAM ratio... where????

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Weeman

Member
Joined
Nov 5, 2009
I've finally got my processor where I want it, and it passed a good couple of hours on prime 95. The issue is that now my sometimes when I load up a IE or view and image in IE it'll freeze up. I'll have to close and restart the program. My guess is the memory isn't stable. The memory PC2-6400 (400MHz), and it running 1 : 1 with the FSB. I'l love to slow it down to 6:5 but I can't find where in the BIOS to find the settings. I've read the manual cover to cover a couple of times with no mention. I'm all up for trying something else to stabilize the RAM too...
Thanks in advance.

Specs:
CPU: Q9550, FSB 470 x 8 Vcore 1.344V
RAM: PC2-6400 1.8V Patriot low latency 2GB x 4
MOBO: Asus P5Q-E BIOS Version 2001
 
First of all you can't slow down the effective DRAM frequency any further than a 1:1 ratio w/ the FSB. If your RAM won't run stably at it's current 470MHz (DDR2-940), raise the multiplier to 8.5 and lower the FSB to 440MHz. The FSB : DRAM ratio is a combination of FSB Strap to North Bridge and DRAM Frequency; there is no actual ratio setting available. Different straps offer different available DRAM frequencies, and the BIOS works out the ratio's for you depending on the NB strap selected. For example at a FSB of 440MHz select either the 333 or 400 strap, and you'll notice the DDR2-880MHz DRAM Frequency setting is a selectable option, which works out to be a 1:1 FSB : DRAM ratio (333/667 NB strap).
 
Thanks for the fast responce. My multiplier is locked so I can't change it. Can I up the voltage or add a cooler? Or do I just need to get faster ram?
 
Like jaymz mentioned, the multipliers x8.5 and downward are unlocked, evidenced by the fact that you're currently running at 470MHz x 8.0 vs the default x8.5 multiplier. As long as Ai Overclock Tuner is set to Manual, the CPU Ratio Setting option can be changed back to the default of x8.5.
 
sorry that was my mistake, the multiplier is 8.5; my bad. but back to the northbridge strap... I've seen this in the BIOS, but have no idea what it does. I gotta be honest redduc900, I don't really understand the instructions. how does lowering the FSB allow me to keep the 4Ghz speed? I think this comes down to my complete lack of knowledge realize my knowledge is limited, really I'm just getting into this stuff.
Thanks again
 
Let's start over again... your current FSB of 470MHz x a default x8.5 multiplier = 4.0GHz. Like I mentioned in my first post above, you can't slow down the effective DRAM frequency any further than a 1:1 ratio w/ the FSB. So at the current 470MHz FSB using a 1:1 FSB : DRAM ratio, this results in an effective DRAM frequency of 470MHz (DDR2-940), which is well above the rated 400MHz. The first thing you should do is run Memtest86+, and see if it's stable at that frequency (any errors mean the modules failed for whatever reason). When Memtest fails, it can be caused by any number of things, for example insufficient Vdimm, timings set too tight, insufficient or excessive vNB (vMCH), incorrect Vcore for a particular clock, etc. And you might want to check out the overclocking sticky at the top of the Intel CPUs forum, which should answer most all of your questions regarding overclocking your quad...

HOWTO: Overclock C2Q (Quads) and C2D (Duals) - A Guide v1.7
http://www.overclockers.com/forums/showthread.php?t=515316
 
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