Blue Screen error message on startup when OC'ing

smartkid95

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I've been overclocking ahlons for a while but now I'm taking a crack at overclocking a pentium dual e2140, I've seen several people have some great results but I can't go past 1770mhz without a physical memory dump error message. I haven't found a post yet that satisfies me. I have windows xp. Why does it do that, is it bad, how do I stop it and can I overclock further, my temps are fine, and stability seems fine so far. any advice?
 
Solution
What kind of motherboard?

Definition time (attention purists, I'm simplifying a little :)):
Core2 CPU's use a frontside bus (FSB). The FSB is a thing with two main characteristics: speed which is usually defined in MHz and width which in the Core2's is 64 bits wide. We are concerned with the speed.

Using the Q6600 as an example, the FSB frequency is 266 MHz. The matching DDR2 memory clock for that frequency is 533 MHz (266 X 2). DDR2 memory transfers two chunks of data for each bus cycle, hence double the frequency.

The FSB clock is 1066 MHz (266 X 4). The bus is "quad pumped". It transfers 4 chunks of data into and out of the CPU each cycle.

Now, if you increase the FSB frequency to 333 MHz, the corresponding memory clock is 667...
Stability is not fine. If it were, you wouldn't be blue screening.

System specs - especially motherboard and RAM?

My Core2 OC links:

This should be your first stop.
HOWTO: Overclock C2Q (Quads) and C2D (Duals) - Guide v1.6.1
http://www.tomshardware.com/forum/240001-29-howto-overclock-quads-duals-guide

This should be your second stop. You need to know something about thermal management or you can fry your CPU. It's pretty difficult to fry a modern CPU, but it is possible.
Core 2 Quad and Duo Temperature Guide
http://www.tomshardware.com/forum/221745-29-sticky-core-core-temperature-guide

Third stop will be a guide for your particular motherboard. Google is your friend.

If you have a Gigabyte 975 - P45 board (the BIOS's are all similar), this may be useful:
Shadow's Gigabyte motherboard OC guide:
http://www.tomshardware.co.uk/forum/page-245679_11_0.html

You will need better cooling. Here are two under $50 heatsinks that are pretty popular:
Sunbeam
http://www.newegg.com/Product/Product.aspx?Item=N82E16835207004
Xigmatec Dark Knight
http://www.newegg.com/Product/Product.aspx?Item=N82E16835233029

They both require a somewhat different approach to applying thermal compound.
Suggestions for applying thermal compound:
http://benchmarkreviews.com/index.php?option=com_content&task=view&id=170&Itemid=1&limit=1&limitstart=5

And they are pretty large, so they might not fit inside your case.

And here's a good budget cooler:
http://www.newegg.com/Product/Product.aspx?Item=N82E16835186134

If you are getting a memory dump error, you may be trying to OC the memory. I don't think that's a good idea for a Core2 system. Run the memory at 1:1. The BIOS should have a memory clock multiplier (or something like it). Take it off AUTO and change it to 2.00. That way, the memory clock will always be twice the FSB freq.

We discuss memory overclocking in this thread:
http://www.tomshardware.com/forum/251715-29-ratio-myth

This will hopefully go a long way to solving your problems.

Keep in mind that these are guides, not cookbooks. YMMV. Your Mileage May Vary. Because of all the variables, you may not do as well as someone else with a similar system. Or you might do better.
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Overclocking since 1978 - Z80 (TRS-80) from 1.77 MHz to 2.01 MHz
 

smartkid95

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For some added detail my memory clock is 666 and fsb was 880 they should be equal?
 
What kind of motherboard?

Definition time (attention purists, I'm simplifying a little :)):
Core2 CPU's use a frontside bus (FSB). The FSB is a thing with two main characteristics: speed which is usually defined in MHz and width which in the Core2's is 64 bits wide. We are concerned with the speed.

Using the Q6600 as an example, the FSB frequency is 266 MHz. The matching DDR2 memory clock for that frequency is 533 MHz (266 X 2). DDR2 memory transfers two chunks of data for each bus cycle, hence double the frequency.

The FSB clock is 1066 MHz (266 X 4). The bus is "quad pumped". It transfers 4 chunks of data into and out of the CPU each cycle.

Now, if you increase the FSB frequency to 333 MHz, the corresponding memory clock is 667 MHz and the FSB clock is 1333 MHz.

I always run my memory at 1:1. That is the FSB freq to memclock ratio is one to one. That means that the memclock is twice the FSB freq.

So your FSB frequency is 220 MHz and your FSB clock is 880 MHz. To run at a 1:1 ratio, your memory clock would be 440 MHz.

With a little bit of luck, you should be able to increase the FSB freq to around 280 - 300 MHz. which would give you a core speed of arond 2.2 - 2.4 GHz.
 
Solution

smartkid95

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I have a xfx motherboard 630i running single channel memory supposed to be 2gb. thanks for the advice it cleared up some of my problems. I'm gonna try it.