cheers i got confussed- lol i thought it got moved to off topic, typing b4 i think again

Thats my thread your talking about, lol

Anyway i volunteer for testing any OCing application

Bring it on!!!!!

On topic:
It's certainly possible to overclock it. I found this thread on the Motorola Droid that uses the same processor and is overclocked to 1 GHz

http://alldroid.org/viewtopic.php?f=312&t=1637

that doesn't tell a thing really. if couple droids can handle 1GHz, one shouldn't draw any conclusions...

I give only one point: physical layout. what are the possibilities that droid and n900 opened are 100% similar?

I don't expect to overclock it stable at 1ghz on the N900. (Although would be cool)
But from what I can see, 800mhz is easily possible and very stable with this CPU.
That would make EasyDebian and emulator games etc run MUCH better imo.

I come from the overclocking world of PCs. I know that EVERY CPU is always overclockable. So I'm sure N900's CPU can.
There is always at least 10% to 50% headroom at stock voltage and temperature so that they are stable at the rated clock 100% of the time.

The fact that N900 can run at 600mhz constant for hours on end tells me straight up that it can easily run at 700-800mhz without issues also.

The N900 scales up to 600 MHz on demand. Locking it to 600 MHz is dangerous to the electronics (because of heat?) according to Nokia. So, no overclocking, unfortunately.

That's not true at all. The ONLY reason it clocks down to 250mhz is to save power. Nothing else.
When I play videos on my N900, it runs at 600mhz constant. For hours. Zero issue.

If what you said was true, it would be very scary indeed and every N900 is 100% guaranteed to crash/fail very often.
I can only assume that you obviously don't know about overclocking and how CPU's are manufactured.

Does it? Videos use the DSP, and (at least on N8x0) DSP max clock wasn't available with CPU at max clock. I don't know about the N900, though.

The overclocking warning came from Nokia at some point (I think it was on the Maemo Summit 2009). The OS does not lock the CPU to 600 MHz and you shouldn't either.

You're right. I don't care much about overclocking. I'm a software guy.

Well, you will find that N900 goes up to 600mhz and will stay there if it requires it. I only use mplayer and noticed it when I was playing it in the background. Also, I'm pretty sure it stays at 600mhz locked when playing game emulators. It would be too slow if it ever clocked itself down while playing.

At the end, if you manufacture a cpu to be run at a certain frequency for even few seconds / minutes at a time in a commercial device, you have to ensure that it can be run at that temperature for much much longer than what it was designed to do.

I don't know of any CPU/chip which cannot handle faster speeds when overclocked. The limiting factor is usually heat and/or voltage. I've been overclocking since the Intel 486 cpu. Every Intel/AMD cpu since then, I've overclocked at least 20% to 80% faster. My current Intel quad core CPU is overclocked from stock 2.4ghz to 3.2ghz. This is considered very "light" overclocking as this cpu can go up to 4ghz if pushed a bit harder.

I just wish I was knowledgeable enough to create an overclocker app for the N900. Unfortunately, I'm not. So I really hope that someone does.

Again, we repeat: a Nokia engineer said clocking it at 600Mhz is _dangerous_. Now, if you feel smarter than the guys who dsigned the device and have the specifications at hand...

And no, it doesn't stay clocked at 600Mhz as any powertop session is going to quickly reveal. EDIT: Note that it seems it doesn't stay clocked at 600Mhz because of the SGX, and without using it, you can happily let it clock at 600Mhz. See a few posts below.