F3-12800cl9d-8gbrl & asus m4a77td

[quadrajet71]

Current build

Asus M4A77TD
AMD Phenom II 965 Black Ed.
2x F3-12800CL9D-8GBRL (16mb)
Win. 7 64

I purchased a set of F3-12800CL9D-8GBRL and installed them with no problems at all. I was able to easily move from 1600 Mhz to over 1700 Mhz. I decided to purchase a second set to give me a full 16mb, but I have had multiple issues trying to overclock. Let me start with that both sets together run fine at their advertised speeds and settings. It is just when overclocking starts.

I have narrowed down one of the new sticks that will not move beyond 1600 at all, not even a little. I get boot lockups along with blue screen memory dumps. I tried bumping the voltages from 1.5 to 1.65 in increments, but still would not work. With the slower stick removed I can run 12mb with the three sticks no problem.

At this point I am running stable with 1448Mhz with 8-8-8-24 timings. Did I just get lucky with my first set... or is it common for one stick to just not keep up?

Any suggestions or ideas would be appreciated.

[Tradesman]

Have you run memtest to see if any errors, if none might want to try about 1.6 and raise the CPU/NB .05 to .09 or so.....

[NemesisChild]

Do you have the C2 (140w) or C3 (125w) revision/stepping 965?

[quadrajet71]

I have run mem test. If it is OC'd multiple errors. When running at stock speed, none.


I have the 125W Stepping 3. Currently running at 1.375v 3672MHz.

[NemesisChild]

May just have to accept that you've reached it's overclocking limit.
I also have found that C3 Denab chips have difficulty with stability over 1600MHz with all dimms populated.
No sweat with only 2 slots populated, but all four dimms puts excessive stress on the Denab IMC.

Much different story with the Thuban X6's, you can easily hit 2000MHz with these CPU's.

[quadrajet71]

I guess I have just pushed it as far as it is going to go with the MB, CPU, and Memory combination. I appreciate the suggestions and I will continue tweaking.

[Tradesman]

Let us know if you find a sweet spot during your tweaking, sometimes you may get nothing at say 1610-1626 then Boom, you hit a spot say 1627 that is fine or even a small range 1627-1633 that all is good, it's weird, but the same often happens with the P35/45 mobos, where you hit black holes in the FSB with nothing then jump up and find a spot