Ive got my n900 running at 1000 mhz.. fixed. If i play a movie it suddenly hangs and reboots. this usually happens when the movie is playing around 3-5 minutes. This is strange because when i play the video via tv out, there is no problem, and the movie plays perfectly to the end. Once rebooted its back at its default kernel with 650 mhz and its all fine...

Does anyone knows wha this is? or is it just a plain overclock unstable reboot thing, since its clearly related to the overclocking of the device?

(is there maybe a way to check a log file, via xterm, for where i can look for errors?)

thankyou.

My guess is that its unstable due to overclocking, or else it wouldn't be fine after rebooting..

Well, mine doesn't reboot even if it's 1000Mhz fixed (but if I enable SmartReflex while at 1000Mhz, it reboots immediately)
Make sure you run the "Ideal" preset and fix it at 1000Mhz. See if it happens again (QCPUFreq helps you)

Smartreflex only works with frequencies <=805MHz.

I can't even get up to 850. The moe I undervolt the worse. I guess the undervolting doesn't agree with the DSP.

Take the setting for 1ghz, and up the voltage-value by one. Save that to your OC profile, and see if that helps.

Seriously, guys... do some custom testing to find values that are /perfectly/ stable; it's not hard.
You may also try changing the DSP clock down a few mhz at the same voltage, see if that helps.

probably because youre profile is unstable, on my device I get a reboot when running ideal for 3 hours. Now I made a profile between lv/ideal and it runs perfectly, the longest uptime was 4 days

use the default settings to overclock
undervolting causes this issue..

A good thing while testing out a profile is to write "dmesg" in terminal to look for potential errors. One of the most frequent is the "dspbridge" loop. That occurs normally when DSP is used like when playing a video or camera.

So 1ghz is not good when it is not needed. To play a video at 805mhz is more than enough (600mhz would suffice). So if i where you.. i would use 805 with enough juice instead. The more mhz -> the more volt is needed. You would probably need overvolting to use video on 1ghz... and that will probably render in overheating eventually and a new battery purchase by you.

thanks, ill fix it at 850 and check if that fixes the problem

//offtopic
There is, obviously a significant difference in performance when i put it at 1000 mhz. but somehow i cant really notice the difference in battery life. this is because i didnt up the voltage?