Monday, October 11, 2004

Quantum Computing

Interesting articel!. As it says, the future computer will not be based on tiny semiconductor gates, but will be using atoms' spins as its logic. It forecasts that around year 2030, the width of a single wire in a microprocessor will reach the width of single atom and this is the limit, if scientists do not find other ways for computer technologies.

Computers built using this physics of quantum mechanics will be 1 BILLION faster than a Pentium-III PC. So for applications such as decryptography (cracking up secured code) can be made in minutes instead of months or years. Amazing!

In August 2000, researchers at IBM-Almaden Research Center developed what they claimed was the most advanced quantum computer developed to date. The 5-qubit quantum computer was designed to allow the nuclei of five fluorine atoms to interact with each other as qubits, be programmed by radio frequency pulses and be detected by nuclear magnetic resonance (NMR) instruments similar to those used in hospitals (see How Magnetic Resonance Imaging Works for details). Led by Dr. Isaac Chuang, the IBM team was able to solve in one step a mathematical problem that would take conventional computers repeated cycles. The problem, called order-finding, involves finding the period of a particular function, a typical aspect of many mathematical problems involved in cryptography.

Full article can be read at:
http://computer.howstuffworks.com/framed.htm?parent=quantum-computer.htm&url=http://www.amd1.com/quantum_computers.html

Friday, October 8, 2004

Today's Faster ever-made PC in the world?

Recently, I was browsing to the Internet and google "fastest PC" and got to a site called "Michael's SuperComputers" @ http://www.michaelscomputers.com/. They said it outperforms it's nearest competition 12X faster than Apple's G5 Dual 2.5GHz.

According to the site, the computer is horsepowered with Pentium4 3.6 GHz Extreme edition (I wonder how much this processor cost? In Apr-Jun 2004, I checked the price some online stores it was above $1000 bucks!). The other thing is that they say it uses SATA-X Hyperdrives. I never hear about this SATA-X, but I guess it's a modification of SATA, or the next version of SATA.

For multimedia outputs, they use the top-end VGA card either from NVidia 6800 Ultra or ATI X800E 256 MB and SoundBlaster's Platinum Audigy ZX soundcard for the audio.

I doubt it is the fastest PC now as it lacks PCI-X slots, no information about Firewire2 (800+ Mbps transfer rate), support for dual or multi-core processor (a processor with dual/multiprocessor on single die, which I believe it will be faster than current processor) but you better check it out.

Saturday, October 2, 2004

Internet Radio

Have you tried Shoutcast? It is very interesting plug-in for Winamp. Using the plug-in, you can broadcast the MP3 files being player by Winamp to the Internet. Unfortunately, the method it uses is unicast, meaning that every user that is connected to your server will double the bandwidth usage unlike multicast-based servers. If you know any free MP3 multicast server for Linux, please let me know.

I like it when I tried with my Linux, it is very efficient although for Linux there is command line only (well, according to www.shoutcast.com, you can use XMMS player but I tried it with no success). For every user connected to the server, it opens a thread/worker to give service. The listener itself listens at port 8001, while port 8000 is used to give a website that you can see what song is playing, song history, and statistics (for the admin only - you can set the password for this).

If you are interested, you can try it or pay a visit to my experimental site: mlutfi.homelinux.org

Myths about NOR and NAND Flash

Myth 1: NAND Flash is slower than NOR.
The Reality:
The performance characteristics of NAND Flash are: fast write (or program) speed , fast erase speed and medium read speed. This makes NAND Flash ideal for low cost, high density, high speed, program/erase applications. Read More

Although NOR Flash offers a slight advantage in random read access times, NAND offers significantly faster program and erase times. For high performance data storage requirements, such as storing digital photos, downloading music and other advanced features popular in today's cell phones, the write/erase speeds of NAND provide a distinct performance advantage. This high performance is also what has made NAND Flash cards so widely used in data storage applications such as digital cameras.

Comparing the time required to perform a typical program and erase sequence for NOR and NAND Flash, for a 64KB erasable unit of memory, NAND outperforms NOR by a wide margin, at 17 milliseconds for NAND, and 2.4 seconds for NOR. In a system application, this difference is large enough to be easily noticed by the user. For the read function, the NAND performance is sufficient to support the system requirement, without a noticeable delay for the user.

Today, many designers build upon the conventional cell phone memory architecture by increasing density of the NOR and PSRAM, and adding NAND Flash to obtain greater performance and capacity for data storage.

Myth 2: NAND is not reliable
The Reality:
Just as a hard disk drive is widely accepted with little concerns about bad sectors, NAND works in a similar way in that the controller maps around bad memory areas and error correction code (ECC) is used to correct bit errors. All controllers for NAND Flash have built-in ECC to automatically correct bit errors. Read More

Myth 3: NAND Flash is hard to integrate into a system.
The Reality:
NAND Flash has an indirect or I/O-like access. Therefore, it must be accessed through a command sequence instead of through the direct application of an address to the address linesNAND Flash also has internal command, address and data registers. Today, a wide selection of NAND controllers and software drivers are available, making integration into a system relatively simple. Read More

Myth 4: MLC NOR is close to matching NAND capacities.
The Reality:
The maximum available density currently available in MLC NOR Flash is 256Mb. The highest available capacity for MLC NAND Flash is currently 2Gb, and the highest available capacity for SLC NAND Flash is 1Gb. Read More

Myth 5: MLC NAND won't hold up under extended use.
The Reality:
MLC Flash has a different rating for the number of read/write cycles compared to SLC NAND Flash. Currently, SLC Flash is rated to have approximately 100,000 cycles and MLC Flash is rated to have approximately 10,000 cycles. However, if a 256MB MLC card can typically store 250 pictures from a 4-megapixel camera (a conservative estimate), its 10,000 read/write cycles, combined with wear-leveling algorithms in the controller, will enable the user to store and/or view approximately 2.5 million pictures within the expected useful life of the card. That number is so far beyond the average number of photos taken by the typical user that the difference in endurance is not significant for this application. Read More

Myth 6: MLC NAND does not have the performance or endurance to reliably store your digital photos.
The Reality:
MLC NAND is rated to have approximately 10,000 cycles, a level that is lower than SLC NAND, but more than sufficient to meet the needs of the vast majority of consumer users. A significant portion of the NAND Flash-based memory cards on the market today are made from MLC NAND, and the continuing rapid growth of this market can be considered an indication that the performance is meeting consumers' needs. Read More

Myth 7: MLC NAND does not have high enough performance for streaming video.
The Reality:
The performance of MLC NAND is sufficient to support the 6 to 8 Mbits/second, transfer rate needed to store MPEG2 compressed video on a memory card. This works out to approximately 1MB/second. MLC NAND can transfer and write approximately 1.7MB/second.

Myth 8: SLC NAND is a generation ahead of MLC NAND.
The Reality:
On Toshiba's roadmap, SLC development leads MLC by only two to three months. Presently, for each new generation, SLC chips are designed with MLC requirements in mind, so there is little lag-time between the two types of NAND. Read More

Myth 9: The additional circuitry needed for MLC NAND takes up a significant amount of real estate.
The Reality:
The circuitry required for MLC NAND is relatively minimal. A 4Gb MLC NAND Flash chip provides approximately 1.95 times greater density than a 2Gb SLC NAND chip. We believe that the more important question to the user is "what density can you get in a chip today?" Presently, the highest density MLC NAND Flash in production is 4Gb, whereas the highest density SLC NAND in mass production is 2Gb. The market demand for ever-higher densities of removable storage makes the lower-cost, higher density MLC card attractive to users and continues to enable new applications to emerge. Read More

Myth 10: NAND Flash is a slow storage technology.
The Reality:
NAND Flash offers excellent performance for data storage. As a point of comparison, it can offer significantly faster performance and reliability than a hard disk drive, depending on the number and size of files transferred. For a random access of a 2kB file, a typical hard disk drive might take approximately 10ms to retrieve a file, while NAND Flash would take about 0.13ms to retrieve a similar size file. For a comparable write function with the 2kB file, NAND could be as much as 20 times faster. Because it is a solid state memory with no moving parts, NAND flash features a significantly shorter random access time compared to a mechanical hard disk drive.


Wednesday, September 29, 2004

Should I buy a new Flash Memory now?


Good question. Based on recent ads, the prices of flash memory have tumbled significantly compared to few months ago. One of online merchant I visited (www.tigerdirect.com) even offers $9.99 for 256 Kingston CompactFlash memory (I guess it is 1x speed).

Depends on your need, the price range can go from US $9.99 up to couple hundreds of dollars for the top memory (such as 4 GB, 40x speed). The speed plays a big role in pricing. The access speed (read/write) factor is similar to CD drive (150 KB/sec is for 1x speed, 300 KB/sec is for 2x speed so on). The new high speed CF sometimes is called CF II.

One thing I still hate to see is there are too many variants and different standard of flash memory. There is CompactFlash I/II, there is Memory stick, MemoryStick Pro, MemoryStick Duo, SmartMedia, SmartDigital, MM and what else, I don't remember. Why don't these people just make one single standard then our life would be better, isn't?

For people who are eager to see and compare the prices, check www.shopping.com, www.dealtime.com, www.mysimon.com, www.techbargains.com, or www.ebay.com. There are many other online shopping comparation portals but I cannot list them all here. Just search them at google, you will see many of them. Comments from previous buyers on these sites are many times useful. The more buyers put comments, the more confidence (or inassurance) you may get. Just check them out!