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I am thinking of increasing the RAM since I will run Mathematica and its memory hungry for more complicated calculations. The slot is only one and the 4GB RAM are too expensive so the only choice is 2GB RAM.
On the other hand, 8 GB memory cards are cheap as hell. Is it possible to make Windows XP use that for RAM and is it going to be effective. I can imagine setting a big page file on the memory card if that is possible. My Sammy went back for a HD swap so I can’t test that idea but am curious. If it works its GREAT!
I’ve read somewhere that 32 bit hardwared/windows has a maximum ability to adress (i.e. to recognize and use) 4GB including the memory from the video card, RAM, all other device meory etc. If that is the case would my Windows XP let me use the whole 8GB ram?
What the experts think?
Vista has a feature called Readyboost which effectively shifts the page file to an SD(or other flash memory) card.
I guess you could as a hack try creating the page file on an SD card under XP (as opposed to a secondary HDD which is what I’ve done in the past), what have you got to lose? (apart from your sanity)
The NC10 will accept a maximum of 2GB RAM.
The Intel Atom N270 processor inside the NC10 is 32 bit and so you can only install a 32 bit OS, usually the limit therefore is 4GB total. However it is possible to use more than 4GB of physical memory through the use of PAE (Physical Address Extension). You are still limited to a 2GB module in the NC10 though.
You can’t use an SD card or memory stick as RAM, however it may be possible to put the page file on the card. This may be a bad idea for a couple of reasons. Firstly the page file will be written to a lot and so will wear out the card quicker, secondly I am unsure as to whether an SD card or memory stick will be initialised soon enough into the boot process (or resume from sleep) to be accessed, which may cause problems (unbootable system?).
As PanMan mentioned Vista’s ReadyBoost would be a safer option.
Or just disable the paging file altogether, with 2 gigs ram in XP you’re unlikely to need it.
Even when the paging file is being used it usually needn’t.
Oh believe me I need more than 2GB of RAM 🙂 The calculations I’m currently doing with Mathematica on my Desktop (1.5GB RAM) after a while start writing on the hard drive. I hate that because it slows down the calculation significantly since hard drive read/write is slower than RAM’s. Also, Mathematica doesn’t seem to have an efficient handling of the memory in such extreme situations. I run exactly the same program over and over again cleaning the variables before each run and after say 10 runs it stars writing on the hard drive again. My interpretation is that it doesn’t free the used RAM memory after each run as its supposed to do.
I know about the ReadyBoost and Prefetch in Vista. As far as I understand it they simply use the USB memory card as a cache to store programs data so they start up faster. I don’t think I need the same thing, I need a real-time data transfer (imagine a HUGE matrix of numbers that Mathematica is manipulating) from the processor/RAM to the card and back. Caching is not going to help I think.
I don’t need the huge memory all the time so I may boot windows in the normal way and insert the card only when I need to do my super-calculations 🙂
I checked the specs for the noisy Fujitsu MHZ 2160BH G2 hard drive I returned for a swap. The Fujitsu site claims data transfer of
3 Gb/s = 375 MB/s !!!
Is it REALLY that fast? I’ve never noticed transfer of 300 MB for one second ??? 30MB/s is more likely.
I also checked the specs of the current memory cards:
http://www.hjreggel.net/cardspeed/
The fastest cards are 20 – 40 MB/s. Of course cards have much better random access than a hard drive cause there isn’t a head to move around.
What do you think after that info update?
[quote1231289169=summertan]
Oh believe me I need more than 2GB of RAM 🙂 The calculations I’m currently doing with Mathematica on my Desktop (1.5GB RAM) after a while start writing on the hard drive. I hate that because it slows down the calculation significantly since hard drive read/write is slower than RAM’s.[/quote1231289169]
Bare in mind that the Intel Atom N270 processor in the NC10 is quite slow. It is not designed for this kind of use and will probably perform poorly compared with your desktop regardless of how much RAM it has.[quote1231289169=summertan]I checked the specs for the noisy Fujitsu MHZ 2160BH G2 hard drive I returned for a swap. The Fujitsu site claims data transfer of
3 Gb/s = 375 MB/s !!!
Is it REALLY that fast? I’ve never noticed transfer of 300 MB for one second ??? 30MB/s is more likely.[/quote1231289169]
It has a 3 Gb/s interface, so the connection between the hard drive and the rest of the computer is capable of 3 Gb/s, the hard drive cannot get anywhere near this.[quote1231289169=summertan]I also checked the specs of the current memory cards:
http://www.hjreggel.net/cardspeed/
The fastest cards are 20 – 40 MB/s. Of course cards have much better random access than a hard drive cause there isn’t a head to move around.
What do you think after that info update?
[/quote1231289169]
It looks like you can set the card to contain the page file however every time you reboot it will most likely be reset back to the hard drive, additionally according to some forum posts under load it may cause system instability (crashes). I wouldn’t expect to see much of a performance boost, hard drives and memory cards are far slower than RAM.Thinking about it ReadyBoost will probably not help either.
What would be the ACTUAL read/write speed of the Fujitsu hard drive? I need a rough estimate, the ballpark.
If the hard drive and the memory card are comparable in read/write speed the memory card has the advantage it has faster random access. If the hard drive is not defragmented and has to read/write all over the place moving the head, that slows it significantly while there is no such problem with the memory card, I think it accesses every data block at the same speed.
I will try it anyways when Sammy is back. Experiment is better than theory.
I would expect it to be around minimum 30MB/s with a maximum around 60MB/s. Probably average around 50MB/s, that is for sequential reads. You could do better if you put a faster drive in.
A quick test with hdparm gives 62.3 MB/s for buffered disk reads, compared to an allegedly “hi-speed” SD card which gives me 9.47MB/s.
If you are looking at SD cards to use the card reader then I would say the fastest you could get would be around 30MB/s read and 15MB/s write.
Personally I wouldn’t trust a setup like this for running calculations, this is why I use a desktop system for anything important/intensive. A netbook is simply not designed for this, even my 4+ year old laptop performs better.
Well I’ll try it and see what happens. I can do the calculation on my 3 years old Presario laptop which appears slower than the Sammy.
Is there a speed limitaion if I use the SD card slot in the Sammy instead a USB card reader? I mean limitation from the slot itself not the card.
[quote1231293280=summertan]Is there a speed limitaion if I use the SD card slot in the Sammy instead a USB card reader? I mean limitation from the slot itself not the card.[/quote1231293280]
Technically the inbuilt SD card reader is connected via USB, that said it my be a bottleneck.
If you use an external device you would need to be very careful not to knock it.It will be interesting to see how well it works, or even if you can manage to permanently trick Windows into letting you place the pagefile on a removable drive (and survive a restart/standby).
I just tried with my desktop which runs Windows XP Home too.
First, every drive has a separate page file. Control Panel does not have an option to put the page for the C: drive (where my Windows partition is) on the USB drive.
So I chose ‘no page file’ for C: and put page file only on the USB drive. You have to reboot for it to take effect. After reboot, the page file for the C partition was restored to where it was before. I guess it doesnt work to completely remove it so maybe I will have to set it to some small value, hoping windows will use the page file on the USB drive. Thats the bad news. The good news is that the page on the USB was still visible after restart.
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