D975XBX2 loses memory timings

[aleph6]

Every few months, my D975XBX2 system "forgets" its memory timings and falls back to 5-5-5-18 at 800MHz. This is a problem because my system won't boot with the memory at 800, and I need to go into the BIOS and set the timings back to my settings. When this first happened, I wasted time diagnosing my overclock, but now I know to jump straight to the memory settings and correct them.

Has anyone else experienced this?

[Pez D Spencer]

What's the speed of the memory you're running? What are your reference clock and memory clock settings? What are your timings? If you set the timings too agressively or your FSB causes your RAM to overclock too much then the BIOS will reset them to the SPD timings/speed.

Here's a good calculator:
http://www.peakin.com/xbx2/calculator.html

Remember to put the base speed of your FSB in the box and not the actual FSB speed (i.e. you would put 266 in the FSB box and not 1066).

I've got a 975XBX2 mobo, a Q6600 @ 3.0GHz (9 * 333MHz), and 2GB DDR2 800. My reference clock is 266 and I have to put my memory clock down to 667. However, by the time the OC'd FSB overclocks the RAM, the RAM ends up at DDR2 833 speeds.

Maybe you already knew all this, maybe you didn't. Either way, hopefully this helps.

[IRQ Conflict]

Disable 'Watchdog'.

[aleph6]

The CPU is an E6400 modestly overclocked to 2.58 (8 x 323). Four gigs of PC2-6400 memory set to 533 MHz. Reference freq is set to "default" which I believe is 266. CPU volts are default (which lets me use speedstep); memory is 2.1, FSB is 1.275, MCH is 1.525.

When I first started playing with this system I read advice to "disable watchdog"; however, if I did so and the overclocked failed, I had to open the case and move the jumper. That seemed to be the only "advantage". Does disabling watchdog somehow help make the overclock more stable?

[IRQ Conflict]

Watchdog is what will reset all the defaults automatically upon system failure in case you set something wrong. It isn't a prefect tech and I prefer to OC without it.As you've noted it resets your memory and can be quite frustrating.

Once you have everything set and running you will no longer need to play with the jumper. Just be careful not to be overly aggressive in your settings.