Crank it up i say! If it breaks get a new one! I bet by the time (if) it does break there'll be a better phone out by then anyway? I hate to say this but it is only a phone? My n900 is awsome but as a phone its useless. The amount of bugs on incoming calls is unexcepable in this day and age and because i'm with voda, making a call is just as bad. I see my n900 as a little computer and i won't loose any sleep over it if it dies. I'm overclocked up to f**k and i can't go back to how slow and juddery it was at stock. Its as smooth as a babys butt now. I believe there's another phone out there (HTC i think) with the same processor runnin 803Mhz or summot? If thats true I'm sure its completly safe to run ours at 800Mhz - 900Mhz.

Based on an article at wikipedia, the official speed of OMAP3430 is 600MHZ
http://en.wikipedia.org/wiki/Texas_Instruments_OMAP

OK, looking at that page... The archetecture/chip design can be run at 1ghz - Though TI used a smaller process to reduce power usage.
At the very least, you can get 800mhz safely out of it - the only difference in the omap 34xx series appears to be binning.
Which means what we knew all along: 800mhz is easily possible and will run on -most- n900s. 1ghz is also possible, but requires overvolting in most cases.

Nokia's stock kernel is quite generous with voltage as well.

I use only 1.215v for 900mhz, but the stock kernel is 1.350v for 600mhz.

If you are undervolting AND overclocking, it greatly mitigates any possible heat increase anyways.

Also remember, we're dealing with heat dissipation of less than 1 watt for the system-on-a-chip's power use. The wireless chip will generate more heat than the CPU.

My 2 cents worth..
Titan's kernel, ulv 250-1000 for 5 months now..
No problems far.

well, what is the relative cpu temperature that is acceptable to cost minimal-no repercussions to the processor?

Using the CPUfreqUI and the Qcpufreq, I checked that the temp regulates from as low as 22-39 (regularly at 30) degrees celcius... as I'm typing now, it's at 25..

as usual, when charging, it's hot, when running many apps, it's usually above 30 but only once have i seen it at the ranges of 38+

I live in the equator and it's a bit cool this time of the year... just wondering what are the acceptable EXACT ranges of temps for the cpu to run smoothly without damaging it

Has their been a program for "Overclocked" users that shut down device or switch settings to a mode that helps the device cool down automatically?

ive got up to 43 degrees celcius, no problem.

starving @ 1150 for months now

my n900 reached the temp of 48c once.....nd dat time instead of takin out da battery to cool it i just left it on da floor(i know it was a foolish idea :P but dat time i completely forgot everything else) the mobile indeed became super hot for few minutes...i was really worried bout my beloved n900 dat tym but still working fine with out any problems just like it was b4 wen i just got it

I live in india that too close to coastal area.In my observation indeed there is an influence of external temparature on the device.In hot summer months my 1.5Ghz device was hot as hell,my battery drained very fast.But in cool environment , my N900 is freezing my cheek.Anyways 1000Mhz is a safe bet.