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There are several obsolete and semi-obsolete models of computers and laptops that are pretty reasonably prices and still has a lot of value in education. Among them Dell Latitude laptops (C600, C800, C610, C810) and Sun Ultra workstations. Both have very good reliability records and while far to the cutting edge in performance are still adequate for all but the most challenging tasks. The eBay prices for C610 are around $400 for the configuration with 1.2Ghz CPU 512 RAM and 40G hard drive. That's 50% less then any new laptop (there are some laptops that Wal-Mart used to sell for $400 but I doubt that they have the same quality).
Please note that in XXI century desktop actually means a laptop and any "regular" desktops are so overpowered can be a very decent server.
Dell Latitude C610 and C810 laptops are compatible with Solaris x86 and can be installed in dual boot configuration with Solaris 10 as a second OS. Having Solaris x86 available is extremely valuable since it is very cost effective to run Solaris on fast/inexpensive PC hardware.
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Asus chairman Jonney Shih sprang a surprise during Intel's Computex keynote today with the announcement of a $189 laptop.
The notebook measures roughly 120 x 100 x 30mm (WDH) and weighs only 900g. We saw the notebook boot in 15 seconds from its solid-state hard disk. The huge auditorium then burst into applause as Shih revealed the astounding price tag. Dubbed the 3ePC, Shih claimed the notebook is the 'lowest cost and easiest PC to use'. As the crowds rushed the stage, we sneaked off to the Asus stand to take a closer look.
The notebook uses a custom-written Linux operating system, much like the OLPC, though unlike the OLPC, Asus has chosen a more conventional interface. The desktop looked fairly similar to Windows and we saw Firefox running on one 3ePC. A spokesperson from Asus told us that the notebook would come with "an office suite that's compatible with MS Office", though he refused to confirm or deny whether that meant OpenOffice.
He claimed the 3ePC would be available in all areas of the world, not only developing nations.
The low price comes from some interesting design choices, primarily the flash-based hard disk. A disk of today's standard capacity would cost more than notebook itself as we saw with the 32GB Samsung disk, but Asus uses a 2GB disk. We were not allowed to touch the 3ePC so couldn't tell how much of this is left after the bespoke OS is installed.
The CPU also remains a mystery, though Shih said the version on show did have 512MB of RAM. Another version will be available for $299, but nobody could tell us what the difference between the two models is.
For all the latest news and developments from Computex 2007 see: www.pcpro.co.uk/html/computex2007
Turbo Memory is...
(Score:5, Informative)by phantomcircuit (938963) on Thursday June 07, @09:40PM (#19432509)
(http://covertinferno.org/)Intel Turbo Memory lets your notebook actually learn your habits to provide better system response. That's because it stores frequently used information near the processor, where it's more quickly available. Better CPUs run better with Intel Turbo Memory.
This entirely new system innovation for Windows Vista PCs is based on Performance Intel® NAND Flash Memory (like the memory in an iPod* or USB 'thumb' drive), together with supporting software. It works alongside your system's RAM to increase the efficiency of data movement between the processor and hard disk.
http://www.intel.com/design/flash/nand/turbomemory /index.htm [slashdot.org]">Intel® Turbo Memory
Re:Turbo Memory is...
(Score:5, Informative)by Vellmont (569020) on Thursday June 07, @10:25PM (#19432883)
I wonder what makes it notable? Size? cost? speed?
High throughput, low latency. Don't know about cost.
It's basically the perfect hibernate cache that doesn't require power to maintain it's state, and will give near instant uptimes. You could also gain a bit from caching disk reads.
It seems a large enough main ram would invalidate this or even the mere presence of on chip cache.
RAM is volatile unless you constantly supply power. Because of this you can't rely on the information to still be their when you come back to a full power state.
Basically this little device would allow people to turn off their PC completely, and power it back up into a fully functional state. You can sort of do that now, but it means either maintaining a little power to the memory to maintain state, or spending an interminable time writing out to disk.
Of course, that means that driver writers need to actually support resuming from sleep, which many today don't properly support.
No, probably Vista only
(Score:5, Informative)by Sycraft-fu (314770) on Friday June 08, @02:50AM (#19434417)As far as I can tell, Turbo Memory is nothing more than flash RAM on the PCIe bus. It isn't what does the caching, Vista is. Vista has a deal called "ReadyBoost" that caches data to flash. You don't need this stuff, any fast USB flash drive will work. The USB interface works fine since max transfer rate of flash is pretty low. It is used for its fast access times. Basically Vista does a whole ton of caching, and does it aggressively.
XP has pretty basic caching, it just leaves stuff in RAM. So if you open a program and then close it, XP doesn't actually zero the RAM it leaves it there. Should you open it again before the RAM is allocated for other uses, it'll use that again. Ok, fair enough, but that only helps for repeat launches. Vista does a similar thing, but actually preemptively loads things in RAM. It bases this off of your usage and thus what it thinks it needs to load the fastest. However since RAM is limited as a secondary cache, it'll use flash memory. Not good for large things, since it is slower for sequential transfers than a disk, but great for caching the first part of things. It starts to load off of flash while the drive seeks, then switched to the drive.
It looks like the Intel memory is nothing more than Flash dedicated for this purpose (looking at the laptop card on their page it is just a controller and 2 flash chips). Thus the OS itself will actually need to do the caching. Linux and/or OS-X could of course add this, but it's up to the OS maker, Intel is just providing the memory on which to do it.
HP rejected Turbo memory because it didn't work.
(Score:2, Informative)by Anonymous Coward on Friday June 08, @02:38AM (#19434351)http://news.zdnet.com/2100-9584_22-6188522.html [zdnet.com]
Apparently it's not all it's cracked up to be.
http://www.anandtech.com/cpuchipsets/intel/showdoc .aspx?i=2985&p=4 [anandtech.com]
Apparently just more marketing hype.
Re:Every SLASHDORK needs turbo memory.
(Score:1)by Hal_Porter (817932) on Friday June 08, @01:51AM (#19434135)Unless the Robson spec requires an NDA and custom IDE commands, then we'll hear lots of moaning about WinHardisks.
Hmm, Robson depends one something called ReadyDrive so the OS can hint to tha harddisk what should be cached -
http://en.wikipedia.org/wiki/ReadyDrive#ReadyDrive [wikipedia.org]
ReadyDrive is a feature of Windows Vista that enables Windows Vista PCs equipped with a hybrid drive to boot up faster, resume from hibernation in less time, and preserve battery power. Hybrid hard drives are a new type of hard disk that integrates non-volatile flash memory with a traditional hard drive.
In June 2006, David Morgenstern wrote an article for eWeek suggesting that ReadyDrive might sacrifice data integrity for speed and battery savings.[2]
The drive-side functionality will be standardized in ATA-8
Looks like Linux will need to wait for the standard, unless Microsoft are feeling generous.
64-bit Futures Part III - IBM and Sun
Well, Power architecture is increasingly going head-on against Itanium in many large deals, even sinking the good ship Itanic in some situations with - believe or not - lower prices! And improved performance with better compilers, more superdense high-bandwidth machine like the superb p655+, where two 8-way single MCM systems with 1.7+ GHz POWER4+ processors fit within a 4U space! So, 16 systems and some 880+ GFLOPs of peak 64-bit power get squeezed into a single rack - 4 times the density of HP Itanium2! Put a nice shared-memory interconnect like the increasingly popular Bristol product, Quadrics QsNet, and you got a nasty supercomputing monster.And, these can run 64-bit Linux (almost) as well as their home OS, AIX.
The memory bandwidth of each eight-way box is 51.2 GB/s, or eight times that of a four-way Intel Itanium2, or 11 times that of a four-way Sun USIII box. Of course, Rmax (the obtainable percentage of FLOPS in Linpack FP bench) is right now far less on Power4 than on Itanium2 - 60% vs almost 90% - but the extra frequency and greater memory bandwidth more than make up for that in many apps.
Towards the end of the year, the multithreaded POWER5 will also dramatically improve the FP benchmark scores, not to mention twice the CPU density, a quarter larger cache, even higher memory bandwidth and lower latency. But don't expect major clock speed improvements, the focus was on real performance and reliability benefits - as if chip-kill memory, eLiza self-healing, and per-CPU logical partitioning was not enough...
Finally, the existing SuSE and coming RedHat Linux on POWER4 and its follow-ons, natively 64-bit of course, aim to give extra legitimacy to it being "an open platform" at least as much as Itanium is.
On the low-end, the PowerPC 970 - or POWER4 Lite, might (or pretty much will be now that Motorola G5 is down the drain) the basis of Apple's next generation Mac platform - it's 64-bit ticket to the future. With its low power - down to less than 16W in low-power mobile 1.2 GHz mode, it will also enable very dense server blades and of course POWERful 64-bit ThinkPads or PowerBooks running AIX, Linux or MacOS...
For IBM then, Opteron makes sense as an excellent tool to corner Intel, with POWER on high end and Opteron on low-end, both 64-bit and both soon manufactured by IBM Microelectronics? No, I didn't say both owned by IBM, even though that is a possibility: AMD does need a sugar daddy, not a sugar mommy. Got my hint who the feisty "sugar mommy" could be?
What about the other major vendor, from SUN-ny California? Well, UltraSPARCIIIi is finally out, no surprise there, it helps a bit but is still far behind all other major CPUs (except MIPS) in most benchmarks. Yes, Sun's mantra of something like "we don't care about speed, we focus on our brand etc" can continue, but what is computing if not about speed and performance?
Still no sign of US IV anyway, and even when it comes, don't expect much of extra per-thread performance over US III - When (and if) it really rolls out in volumes towards yearend, it will have to fight both POWER5 and Madison2, both very powerful beasts on the rise, backed by humungous ruthless megacompanies - each of which can eat Sun as an appetiser.
You can read hundreds of pages of Net discussions about the particular merits and demerits of SPARC vs other architectures, from all sides and viewpoints, but the fact remains - SPARC is the turtle of the 64-bit world, slow and maybe long-lived compared to, say, Alpha, but even turtles have to die at some point... and before they die, they become extremely slow...
64-bit Opteron is fast in some things compared to the rest of the gang, and not so fast in others, but whatever the case, current and future Opterons are vastly superior performance and feature wise to low-end and midrange SPARC offerings at umpteen times lower cost. Plus, they are as 64-bit as SPARC (or any other 64-bit CPU) is... so Sun taking Opteron would be simply common sense...
THIS ARTICLE hopes to cast some light on why 64-bit addressing, that is, the native mode of the Opteron or Itanium versus that of the Athlon or Pentium is important in 2003. It also attempts to address what the requirements are and - equally importantly - are not.Before we start, an easy one. Why 64-bit and not 48-bit? Because it costs little more to extend a 32-bit ISA to 64-bit than to only 48-bit, and most people like powers of two. In practice, many of the hardware and operating system interfaces will be less than 64 bits, sometimes as few as 40 bits, but the application interfaces (i.e. the ones the programmers and users will see) will all be 64-bit.
There are several non-reasons quoted on the Internet; one is as arithmetic performance. 64-bit addressing does not change floating-point, and is associated with 64-bit integer arithmetic; while it is easy to implement 32-bit addressing with 64-bit arithmetic or vice versa, current designs don't. Obviously 64-bit makes arithmetic on large integers faster, but who cares? Well, the answer turns out to be anyone who uses RSA-style public key cryptography, such as SSH/SSL, and almost nobody else.
On closer inspection, such use is dominated by one operation (NxN->2N multiplication), and that is embedded in a very small number of places, usually specialist library functions. While moving from 32 to 64 bits does speed this up, it doesn't help any more than adding a special instruction to SSE2 would. Or any less, for that matter. So faster arithmetic is a nice bonus, but not a reason for the change.
File pointers are integers, so you can access only 4GB files with 32 bits, right? Wrong. File pointers are structures on many systems, and files of more than than 4GB have been supported for years on a good many 32-bit systems. Operations on file pointers are usually well localized and are normally just addition, subtraction and comparison anyway. Yes, going to 64-bits makes handling large files in some programs a bit easier, but it isn't critical.
Let's consider the most common argument against 64-bit: compatibility.
Almost all RISC/Unix systems support old 32-bit applications on 64-bit systems, as did IBM on MVS/ESA, and there is a lot of experience on how to do it almost painlessly for users and even programmers.
Microsoft has a slightly harder time because of its less clean interfaces, but it is a solved problem and has been for several decades.
Now let's get onto some better arguments for 64-bit. One is that more than 4GB of physical memory is needed to support many active, large processes and memory map many, large files - without paging the system to death. This is true, but it is not a good argument for 64-bit addressing. The technique that Intel and Microsoft call PAE (Physical Address Extension) allows 64 GB of physical memory but each process can address only 4GB. For most sites in 2003, 64GB is enough to be getting on with.
IBM used this technique in MVS, and it worked very well indeed for transaction servers, interactive workloads, databases, file servers and so on. Most memory mapped file interfaces have the concept of a window on the file that is mapped into the process's address space - PAE can reduce the cost of a window remapping from that of a disk transfer (milliseconds) to that of a simple system call (microseconds). So this is a rather weak reason for going to 64-bit addressing, though it is a good one for getting away from simple 32-bit.
Now, let's consider the second most common argument against 64-bit: efficiency. Doubling the space needed for pointers increases the cache size and bandwidth requirements, but misses the point that efficiency is nowadays limited far more by latency than bandwidth, and the latency is the same. Yes, there was a time when the extra space needed for 64-bit addresses was a major matter, but that time is past, except perhaps for embedded systems.
So 64-bit addressing is unnecessary but harmless except on supercomputers? Well, not quite. There are some good reasons, but they are not the ones usually quoted on the Internet or in marketing blurb.
The first requirement is for supporting shared memory applications (using, say, OpenMP or POSIX threads) on medium or large shared memory systems. For example, a Web or database server might run 256 threads on 16 CPUs and 32GB. This wouldn't be a problem if each thread had its own memory, but the whole point of the shared memory programming model is that every thread can access all of the program's global data. So each thread needs to be able to access, say, 16GB - which means that 32-bit is just not enough.
A more subtle point concerns memory layout. An application that needs 3GB of workspace might need it on the stack, on the main heap (data segment), in a shared memory segment or in memory set aside for I/O buffers. The problem is that the location of those various areas is often fixed when the program is loaded, so the user will have to specify them carefully in 32-bit systems to ensure that there is enough free space in the right segment for when the program needs its 3GB.
Unfortunately, this choice of where to put the data is often made by the compiler or library, and it is not always easy to find out what they do. Also, consider the problem of an administrator tuning a system for multiple programs with different characteristics. Perhaps worst is the case of a large application that works in phases, each of which may want 2GB in a different place, though it never needs more than 3 GB at any one time. 64-bit eliminates this problem.
To put the above into a commercial perspective, almost all general purpose computer vendors make most of their profit (as distinct from turnover) by selling servers and not workstations. 64-bit addressing has been critical for some users of large servers for several years now, and has been beneficial to most of them. In 2003, 64-bit is needed by some users of medium sized servers and useful to most; by 2005, that statement could be changed to say `small' instead of 'medium sized'. That is why all of the mainframe and RISC/Unix vendors moved to 64-bit addressing some time ago, and that is why Intel and AMD are following.
On the other hand, if you are interested primarily in ordinary, single user workstations, what does 64-bit addressing give you today? The answer is precious little. The needs of workstations have nothing to do with the matter, and the move to 64-bit is being driven by server requirements. µ
Nick Maclaren has extensive experience of computing platforms
Linuxnewbie.org:
Getting UDMA66 To Work(Jan 11, 2000)
Promise
PDC20262 Ultra DMA/66 supported.(Apr 25, 1999)
WWW Computer Architecture Home Page[July 7, 1999]
Serial Communications -- from FreeBSD textbook
External Parallel Port devices and Linux - Links to External Parallel Port projects and documentation.
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Last modified: October 09, 2008
Re:Turbo Memory is...
(Score:1)(http://covertinferno.org/)
This seems like it would be just as useful as increasing system performance. The advantages being ease of installation and cost. The disadvantages being lower performance than standard system RAM.
Memory caching at the disk level seems like a much more promising technology