differences between DDR and DDR2

Mar 2, 2009

“Double Data Rate, Two” or simply, DDR2, is an extension of a system’s standard DDR memory. Like DDR, DDR2 transfers data on both edges of the system clock, which allows the bandwidth of the memory to equal twice that of Single Data Rate memory, or SDRAM. DDR2’s architecture is intended to increase efficiency and performance over its predecessor, DDR.

  • DDR’s standard voltage setting is 2.5 V, while DDR2’s voltage setting is 1.8 V.
  • DDR2 memory is DDR2’s 4-bit data pre-fetch. DDR has two sets of data that are read and written to the memory core, while DDR2 allows for four sets of data to be processed.
  • DDR’s write latency is one clock. This allows for data to be written to the memory one clock after the write command has been issued. With DDR2, the write latency becomes two clocks. The doubled clock cycle allows for twice the data to be written to the memory after the write command has been issued.
  • DDR2’s new feature called On-Die Termination (ODT). ODT permits the user to terminate signals in the memory itself. The termination of DDR is done on the motherboard. ODT drastically reduces signal wave reflections from the termination network and promotes enhanced systems margins. ODT permits fewer capacitors and resistors on the motherboard, which helps reduce cost and makes memory subsystem layouts to be more efficient.
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How Spyware Get into your Computer

Spyware gets on your computer in one of several different ways.

  • Along with software you download from the internet and install on your system.
  • Come from email attachments (much like viruses) and automatically install themselves on your computer when you open the email message.
  • Hackers find an open port on your computer and use the “back door” to install basically anything they want.
  • The more malicious types, like keystroke loggers, can even get installed by someone with direct physical access to your computer such as an employer, suspicious spouse, business competitor, or someone who wants to know exactly what you’re doing.
READ MORE - How Spyware Get into your Computer

Intel Pentium M Processor

The Intel Pentium M processor utilizes a new microarchitecture to meet the current and future demands of high-performance, low-power embedded computing, making it ideal for medium-to-large enterprise communications applications, transaction terminal, interactive client, and industrial automation applications. While incorporating advanced processor technology, it remains software-compatible with previous members of the Intel microprocessor family.

The Intel Pentium M Processor on 0.13u process technology is validated with the Intel E7501 and Intel 855GME chipsets. The Intel Pentium M Processor on 90nm process technology is validated with the Intel E7501, 855GME, E7520, E7320 chipsets, Mobile Intel 915GME Express Chipset and Intel 3100 (see table for details). These unique platform combinations help address a variety of customer requirements.
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Intel Celeron Processor 440

The Intel Celeron processor 440 balances proven technology with exceptional value for embedded computing designs such as print imaging, gaming, interactive clients, and industrial automation. Featuring Intel Intelligent Power Capability, it supports smaller, quieter, more energy-efficient embedded systems with improved performance over previous Intel Celeron processors.

Manufactured on 65nm process technology, the Intel Celeron processor 440 at 2.0 GHz offers 512 KB of L2 cache with a thermal design power (TDP) of 35 watts. Based on a new energy-efficient microarchitecture, this Celeron processor enables smaller and quieter embedded designs. It features Execute Disable Bit (for built-in security support) as well as Intel 64 architecture (Intel 64), enabling applications to access larger amounts of memory when used with appropriate 64-bit supporting hardware and software.

The Intel Celeron processor 440 is available in an LGA-775 package with integrated heat spreader. When combined with the Intel Q45 Express Chipset, Intel Q35 Express Chipset, Intel Q965 Express Chipset or Intel 3210 Chipset, the platform provides exceptional value with mid-range performance and reduced power.
Product information

Features and benefits

800 MHz front-side bus Provides accelerated access to data from the processor core.
Intel Wide Dynamic Execution Improves execution speed and efficiency, delivering more instructions per clock cycle.

Intel Smart Memory Access

Optimizes use of data bandwidth from the memory subsystem to accelerate out-of-order execution, keeping the pipeline full while improving instruction throughput and performance. Newly designed prediction mechanism reduces the time in-flight instructions must wait for data. Pre-fetch algorithms move data from system memory into fast L2 cache in advance of execution.

Intel Advanced Digital Media Boost

Accelerates execution of Streaming SIMD Extension (SSE/2/3) instructions to significantly improve media boost performance on a broad range of applications. 128-bit SSE instructions are issued at a throughput rate of one/clock cycle, effectively doubling speed of execution over previous-generation processors.
Execute Disable Bit° Enhances virus protection when deployed with supported operating system. Allows memory to be marked as executable or non-executable, allowing the processor to raise an error to the operating system, thereby preventing malicious code from infecting the system.

Intel 64 Architecture (Intel 64) Enables access to larger amounts of memory and provides flexibility for 32-bit and 64-bit applications. With appropriate supporting hardware and software, platforms supporting 64-bit computing can use extended virtual and physical memory.
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NVIDIA nForce 730a for AMD

Processor Supported Phenom|Athlon 64 X2|Athlon 64 FX|Athlon 64
Socket Supported AM2+
PCI Express 2.0 yes
HT Speed HT3
DDR Support DDR2
SATA/PATA Drive Support 6/2
NVIDIA MediaShield Storage yes
NVIDIA MediaShield RAID 0, 1, 0+1, 5
Audio Specification HDA (Azalia)
USB Ports Up to 12 USB 2.0 ports
Gigabit Ethernet Connections 1
PCI Express Configuration 3x1, 1x16
NVIDIA FirstPacket technology yes
PCI Express x16 slots 1
PCI Slots 5
NVIDIA Control Panel yes
Vista Support yes
NVIDIA GeForce Boost yes
NVIDIA HybridPower yes
Display Outputs VGA / Single Link DVI
Direct X 10
Form Factor ATX
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How EIRGP(Enhanced Interior Gateway Routing Protocol) is different

  • Advance Distance vector Protocol
  • Support for IP, IPX, and AppleTalk via protocol-dependent modules
  • Considered classless (same as RIPv2 and OSPF)
  • Support for VLSM/CIDR, Discontigous Subnets
  • Support for summaries and discontiguous networks
  • Efficient neighbor discovery
  • Communication via Reliable Transport Protocol (RTP)
  • Best path selection via Diffusing Update Algorithm (DUAL)
  • Fast Convergence
  • Partial Updates
  • Flexible network design
  • 100% Free Classless routing
  • easy Configuration foe WANs & LANs
  • Load balancing equal & Unequal Cost pathways
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How the Packet reach from One point to another on Internet

  1. After the initial TCP/IP three way hand shake has been negotiated, your web browser will issue a request to the web server hosting your homepage asking for its homepage.
  2. This HTTP GET request information now has to be sent to the web server.If you select the write operation it will cause the data that application wants to send to be copied from the applications memory space to the socket send buffer within kernel space.
  3. Depending on what transport protocol the application uses, the socket layer will call either UDP or TCP. Some applications use TCP or UDP as a Transport Layer protocol. DNS uses both UDP and TCP, while other applications such as TFTP will only use UDP. Once the socket layer calls the proper transport protocol, the data will be copied over into a socket buffer.
  4. TCP will fragment this data if required. What happens if the browser’s request exceeds the MTU.TCP itself will fragment the data in order to ensure that the size complies with the Ethernet MTU limit of 1500 bytes. A key point to remember here is that fragmentation will occur at the TCP layer if the application invoked uses TCP as it transport protocol. If application is using UDP then fragmentation will happen at the IP layer.
  5. At Network layer IP header is built and the all important IP addresses are added.
  6. After this, the data then drops down to the data link layer where both the logical link control and media access control layers do their parts. Finally the data is now ready to transmitted by the physical layer as embodied by your NIC card.
  7. Now it reaches to Ethernet Switch
  8. After the packet goes through the switch it makes its way to the router, and may very well go through a firewall prior to the router as well.
  9. At router if required NAT is performed, if you have the Private Address not a public Address
  10. Now the packet travel through the many routers and every router route the packet based on its own routing table information. Once the next router receives this same packet it will consult its own routing table, and send it on its way based on what it considers the best path. Before this happens, the router will change several fields in the IP header of the packet. One of the fields that will change is the TTL field or “time to live.” Now, as part of the IP header has changed, the router must compute a new checksum value for the packet.Finally it reaches to its destination.
  11. The physical layer will issue an IRQ to the CPU indicating that there is data to be processed. Once that occurs, the data is passed up the data link layer where the webserver will recognize the MAC as indeed being its own, and will pass it up to the IP layer. The IP address is in turn recognized as belonging to it so that it then passes the data up to the transport layer where it is put into the TCP buffer. At this point the application notices that the data is for it and it processes the information. The end result of this is that the information requested for in the GET request issued by the client is then sent back.
READ MORE - How the Packet reach from One point to another on Internet

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