N900 Hardware
 

Hi,
source: http://maemo.nokia.com/n900

As we all now, the n900 has a 600 mhz CPU and 256 mb of RAM.
To tell the truth, nokia could give the n900 more advanced and powerful components like: at least 800 mhz CPU and 512 mb of RAM.
Do you find the current spec satisfying?

We expect from the n900 to be a mobile computer, to run multiple applications at the same time and to run kde and other desktop environments. Will the n900 handle all these?


Feel free to reply!

Re: N900 Hardware
 

The 600 MHz CPU and 256 MB RAM are both parts of OMAP3, so you'd have to change the entire hardware in case you're not satisfied with those specs. Also keep in mind that the 800 MHz ARM11 chips are far inferior to a 600 MHz ARMv7 (Cortex A8) chip.

Re: N900 Hardware
 

You do realize this thing was probably designed a year ago. 800 mhz and 512 mb of RAM might be out now, but wasn't available at the time and currently not available in the market now (device for sale). There's a reason Palm, Apple and Nokia have the same hardware.

I would expect the maemo 6 devices to have 512mb of RAM and 800 mhz - 1 Ghz processor given what's sampling now.

Re: N900 Hardware
 

But the idea of an upgradeable processor would be great:D
But even in Laptops we still dont have :mad:

cant ever see it happening until we get MobileATX motherboards;)
(I just made that up)

Mike C

Re: N900 Hardware
 

That would make the costs of producing a cell phone tremendously higher, with little to none benefit.

Re: N900 Hardware
 

If the n900 would have been 800 Mhz / 512 Mb, I bet many would have said that only 1.2 Ghz/1 Gb would be satisfying. You have to remember that:
1. you cannot put to market an embedded devices with today's processors (like others said, the n900 was designed some time ago)
2. You have to power it from a 1350 mA, one cell battery. Get a 1.3 GhzAtom netbook and discharge the battery to 20% and see how much it lasts from there :D It's pretty much what this cpu has to deal with.

Re: N900 Hardware
 

I really hate to be "that guy", but in case it wasn't a typo, just FYI, battery capacity is measured in mAh (mA * hours), which is equivalent to Coloumbs (measure of charge) - not mA. The rating is essentially saying that if your device were to draw 1350mA, the battery would run for 1 hour. (You can split that product up any way you want, e.g. if it draws 675mA, it would run for 2 hours.)

And by the way, I agree with point 2. I'm actually kind of glad that I can't afford a cell plan for an N900, if I manage to get one at all (I've entered the PUSH competition, so we'll see), as I'd probably use it so much as a computer that I wouldn't have enough charge for calls, as it is. IIRC, though, the N900's battery is slightly larger than the 1350mAh battery in the N8x0. Meh... whatever - your point is still valid.

Re: N900 Hardware
 

The BP-5L battery in the N800 is 1500mAh. The battery in the N810 uses BP-4L which is supposed to have the same capacity. So both of the N8x0 models have a higher battery capacity than the N900. Due to the, I believe, improved battery saving capability of the OMAP3 chipset this shouldn't matter too much, except that the GSM/HSPA part of the N900 will suck some juice no matter what.

EDIT: I've found some sites selling genuine Nokia BP-5L batteries and claiming they are 1300mAh. However, Nokia's web pages say 1500mAh, and that fits with what I've heard before and I'm inclined to trust the Nokia site more.

770/N800 battery:
http://europe.nokia.com/find-product...-battery-bp-5l

N810 battery:
http://europe.nokia.com/find-product...-battery-bp-4l

Re: N900 Hardware
 

I wonder if they're the same voltage. Remember that energy = voltage * current * time. 1350 mAh gives current*time, but says nothing about the total energy stored

Re: N900 Hardware
 

They're the same voltage. So-called 3.7V Lithium ion or polymer batteries. These kind of batteries are charged up to 4.10 or 4.20 volts, and are considered empty when dropping somewhere below 3.8 volts (the cut-off on my Palm PDA is 3.76 volts default, with warning messages starting to pop up at 3.78volts). The batteries can be discharged much lower, but will get damaged at some point (there's much more about this on batteryuniversity.com).

Re: N900 Hardware
 

It turned into a physics topic :D

What I originally meant is:
Do you think that the current hardware will be strong enough in order to deal with high requirements applications, like running a high requirements desktop environments and demanding softwares as open office, a web browser, etc simultaneously?

The experienced developers and users of n8x0 might know. Please answer.

Re: N900 Hardware
 

If my memory serves me well, one of the reason of the current 600 Mhz cap is to avoid frying the processor. On one slide of the Maemo Summit there was a prevention to developers about that.

Re: N900 Hardware
 

I think it will, as long as they are tailored to the platform. If desktop applications are just dumped on the N900, the differences in interface (screen size, input method, etc) and power use could make a bad experience.

FWIW, from some raw comparisons here and there, the Cortex chip in the N900 should be very roughly equivalent to one of the earlier Intel Atoms. More physical RAM can't be added, and I am not sure if we can manually add more swap passing the 1Gb default, or if the system can address it properly.

Re: N900 Hardware
 

http://wiki.maemo.org/Easy_Debian
"You need to keep your expectations reasonable. Big desktop applications like OpenOffice and Firefox run slowly on the tablet. They are designed for big, power-hungry CPUs."

Even though the N900 is much more powerful than the previous tablets, the point is still valid. And why on earth would you want to run a desktop environment designed for desktop computers on it?

Re: N900 Hardware
 

How does the N900 arm processor fair against the 1GHz Snapdragon™ processor?

Re: N900 Hardware
 

clock for clock they should be very comparable in raw processing as they are both based on the ARM cortex a8 I believe. At least, that's what I gather from this:
http://www.engadget.com/2009/10/14/c...ehind-android/

Re: N900 Hardware
 

mrojas, thank you very much for answering!
Do you find the 768 mb virtual memory useful and influencive?

That's where all the fun begins! ;)
Just joking. I find the desktop environments (LXDE for example) more usable sometimes. Besides it's much more cool! :D

Thank you for your answers, it's realy helping a lot.

Re: N900 Hardware
 

Anybody who is following the current CPU technology should know that the processors keep getting efficient and faster by the day, but the batteries ain't catching up that fast. To have a usable portable system all the factors (CPU, Battery, Heat, Form Factor etc..) should be considered, sure you can put a GHz CPU inside a full solid aluminum chassis and a huge battery but will it be marketable? I believe the N900 is powered well enough for what it is expected to achieve by most of the users.

Re: N900 Hardware
 

Of course. The reason it multi-tasks so well is because it has the swap. Since the swap is flash based, it is quite fast too (but slower than the RAM).

Precisely one of the reasons why the iPhone doesn't multi-task natively is because it would run out of memory soon (as stated by one Apple developer). So I am guessing other mobile operating systems will add swap soon too, following the cue from Maemo, thus allowing better multi-tasking and "out of memory" errors.

Re: N900 Hardware
 

@mrojas, I have experienced a lot of failures based on flash degradation on various smartphones utilizing flash for storage of vital system information (not removable flash). But since Maemo is Linux, I was wondering if such a scenario happens, can we partition a µSD with a swap and configure Maemo to use that partition (will be slower, but could work right?)

Re: N900 Hardware
 

You can make that happen, but it's quite a bit of trouble for no real gain. You're swapping on a 32GB eMMC device, so, as beaten to death in other threads, there is no realistic chance of wearing that out in the device's lifetime.

Re: N900 Hardware
 

He kinda lost me at "But the Cortex A8 is built using 65nm transistors, which makes it roughly twice the size (and thus twice the cost to manufacture) of an ARM11 core (which has 90 nm transistors)".

Re: N900 Hardware
 

Just replace 'size' with 'area' mentally, the point is it grows as a square. 45nm would have been one quarter of the 'size' of 90 nm.

Re: N900 Hardware
 

I'm pretty sure it means size as in "number of transistors". Smaller transistors on the same-sized chip = more of them. And yes, 65*2 is not 90, because, as it has been pointed out, it's not something linear.

Re: N900 Hardware
 

With regards to the CPU speed, the OMAP3 in the Pandora has been known to happily overclock to 900mhz (cpufreq support for the OMAP3 is in kernel mainline) so with any luck decent overclocks may be possible on the N900 too. One thing to bear in mind though is that the CPU on the N900 has no heatsink, the case has no air vents and you really don't want to fry your £500 phone!!

Re: N900 Hardware
 

Heh. It's been said it fries at 600Mhz already. The builtin CPUFreq forces it to spend most of the time at < 500Mhz frequencies.

Re: N900 Hardware
 

don't forget about the powerVR graphics, and integrated DSP +ISP... I don't know how much they're currently used - but I would guess the situation could be similar to that on PCs - that the additional hardware is even more powerful than the main CPU...

Must be madness to cool down such hardware (it's even cooler to think about that this hardware is probably more powerful than regular pc's were just 10 years ago :))

Re: N900 Hardware
 

Heat isn't really the issue. Overvoltage is.

Re: N900 Hardware
 

Тhats just what i was thinking.Is there any possible way to manipulate the voltages?

Re: N900 Hardware
 

Speaking in very rough numbers, the cortex A8 has about 4 times the number of transistors as ARM11. However, when cortex A8 is manufactured on a 65nm process, the actual size of the chip is roughly twice the size of the ARM11 core when the ARM11 is manufactured on a 90nm process and thus twice as expensive as that ARM11. If they were both manufactured on a 65nm process to maintain an apples-to-apples comparison...the Cortex A8 would be about 4 times as large, and thus about 4 times as expensive to make as that hypothetical 65nm ARM11.

Without going into *too* much detail... large volume IC manufacturing costs are very strongly linearly related to the size of the chips (within the same technology "generation/family" eg SOI, strained silicon, copper interconnects, etc) due to the built-in costs of the wafers they are made from as well as the staggering up-front capital costs for the equipment.

Hope that clears it up a bit.

Re: N900 Hardware
 

As for overclocking, the Pandora overclocking numbers are (obviously) from chips produced earlier. Since then TI has apparently started speed-sorting their chips, and those that can handle a higher frequency go into a bin with a different ID and, presumably, different price (this is fairly normal practice btw). So it may be that on production model Pandoras and N900s there will be fewer of them that will actually overclock well.

Re: N900 Hardware
 

Wafer yield is the other issue. Run into diminished returns at some point. Scrap is a the big nasty here as far as total cost of process. SPC in these processes are always looking at the yield curve of good chips.