RAM

 

 This document describes Value RAM's 256M x 64-bit 2GB (2048MB) DDR3-1333 CL9 SDRAM (Synchronous DRAM) Memory Module based on sixteen 128M x 8-bit DDR3-1333 FBGA components. The SPD is programmed to JEDEC Standard latency 1333Mhz timing of 9-9-9 at 1.5V. This 240-pin DIMM uses gold contact fingers and requires +1.5V.

Features

• JEDEC standard 1.5V � 0.075V Power Supply
• VDDQ = 1.5V � 0.075V
• 667MHz fCK for 1333Mb/sec/pin
• 8 independent internal bank
• Programmable CAS Latency: 5,6,7,8,9,10
• Posted CAS
• Programmable Additive Latency: 0, CL - 2, or CL - 1 clock
• Programmable CAS Write Latency(CWL) = 9(DDR3-1333)
• 8-bit pre-fetch
• Burst Length: 8 (Interleave without any limit, sequential with starting address �000� only), 4 with tCCD = 4
• which does not allow seamless read or write [either on the fly using A12 or MRS]
• Bi-directional Differential Data Strobe
• Internal(self) calibration : Internal self calibration through ZQ pin (RZQ : 240 ohm � 1%)
• On Die Termination using ODT pin
• Average Refresh Period 7.8us at lower then TCASE 85�C, 3.9us at 85�C < TCASE . 95�C
• Asynchronous Reset
• 1066Mbps CL7 doesn�t have backward compatibility with 800Mbps CL5
• PCB : Height 1.180� (30.00mm), double sided component

Performance

• CL(IDD) 9 cycles
• Row Cycle Time (tRCmin) 49.5ns (min.)
• Refresh to Active/Refresh Command Time (tRFCmin) 90ns
• Row Active Time (tRASmin) 36ns (min.)
• Power TBD W (operating)
• UL Rating 94 V - 0
• Operating Temperature 0o C to 85o C
• Storage Temperature -55o C to +100o C
•  

Kingston 2GB RAM DDR2 For Desktop PC800

  

How can I check if my computer has enough RAM?

Before we check current RAM (Memory) usage of your computer, lets define what "RAM" means, what it is and its usage.

RAM is short for Random Access Memory. It is a physical piece of hardware similar to the one shown below that is installed inside your computer. RAM is measured in KB (KiloBytes), MB (MegaBytes) or GB (GigaBytes).

RAM CHIP - DIMM (Dual Inline Memory Module)

How is RAM Used?

RAM's function is somewhat similar to the short-term memory that a human brain uses for all of its computations.

When you launch a program such as Microsoft Word, it is first loaded from Hard Drive (permanent storage) to RAM (short term storage) then executed by your computer. If your computer has a lot of RAM installed, you can run multiple software without slowing things down.

Does RAM store data in it permanently?

RAM is volatile in nature; meaning it requires constant electrical power to refresh itself in order to keep the data contents stored in it. When power is turned off, all data stored in RAM is lost.

How do I check current RAM usage on my PC?

Windows 7/Vista:

Step 1: To check current Memory usage on a Windows 7/Vista computer, right click on Task Bar (Task Bar is the Grey/Blue bar at the bottom of the screen) then left click on "Start Task Manager".

You will see "Windows Task Manager" window. Task Manager shows application currently running on your computer.

Step 2: Click on "Performance" tab within "Windows Task Manager". A screen similar to the following appears. This screen shows Memory and CPU usage statistics of your computer. 

To keep this guide simple, we will note:

• "Total" under Physical Memory; which in this case is 2047MB or 2GB.
• "Memory" Section shows the amount of Memory computer is currently using; which in this case is 1.13GB.
• "Commit (MB)" value in right side column shows the total of Physical RAM and Virtual Memory in MB (Mega Bytes) currently in use; which in this case is 1619MB or 1.58GB.

As you can see, "Total" RAM value (2GB) is more than total Commit value (1.58GB); so this computer does not need a RAM upgrade.

But if "Total" RAM value (2GB) for example was lower than "Commit" value then you should upgrade the RAM.