What is the difference between DDR3, DDR2, DDR, and SDRAM?
Answer: RAM is a kind of computer memory that temporarily stores information, improving your systems performance. Or in other words RAM simply holds data for the processor. The processor also has its own memory known as the L2 cache, the cache lies between the processor and the RAM. The processor sends and retrieves data from this cache, when this cache overflows data is sent to the RAM.
There are mainly four types of RAM; SD, DDR, DDR2 and DDR3. They differ in the way they operate and mainly in their operation speeds. All RAM's used in computers today have a synchronous interface meaning they wait for a clock signal before it can respond to clock signals.
What is SDRAM?
Answer: SDRAM stands for synchronous dynamic random access memory. SDRAM is Single Data Rate meaning that SDRAM can accept one command and transfer one word of data per clock cycle. As mentioned above SDRAM's have synchronous interface therefore they depend on the computer clock signals to perform operations. Typical speeds of SDRAM are 100 and 133 MHz.
What is DDR SDRAM?
Answer: DDR SDRAM stands for double data rate synchronous dynamic random access memory. DDR RAM transfers data twice per clock cycle, hence the name double data rate. DDR clock speeds range between 200 MHz (DDR-200) and 400 MHz (DDR-400). DDR-200 transfers 1600 MB/s, while DDR-400 transfers 3200 MB/s.
What is DDR2 SDRAM?
Answer: DDR2 SDRAM stands for double data rate 2 synchronous dynamic random access memories. DDR2 is twice as fast as DDR which means twice as much data is carried to the module for each clock cycle. Also due to the design improvements DDR2 consumes less power as compared to the DDR memory. DDR2 speeds range between 400 MHz (DDR2-400) and 800 MHz (DDR2-800). DDR2-400 transfers 3200 MB/s. DDR2-800 transfers 6400 MB/s.
What is DDR3 SDRAM?
Answer: DDR3 SDRAM Stands for double data rate 3 synchronous dynamic random access memories. In theory DDR3 is supposed to act twice as fast as DDR2 memories. Thus DDR3 speeds range between 800 MHz (DDR3-800) and 1600 MHz (DDR3-1600). DDR3-800 transfers 6400 MB/s; DDR3-1600 transfers 12800 MB/s.
What is the maximum amount of RAM that Windows operating system can handle?
Answer: Answer: It depends on two factors-
a. The amount of memory your computer hardware [Main board] can handle.
b. The amount of memory your Microsoft® Windows® operating system (OS) can handle.
You can check your main board maximum capacity by using our “Product Compatibility Search” and for your operating system here is the list of the supported memory-
For more, please visit http://www.microsoft.com/whdc/system/platform/server/pae/paemem.mspx
|Windows 7 (32 Bit)
||Windows 7 (64 Bit)
||Windows Vista (32 bit)
||Home Basic: 8GB
||Ultimate: 4 GB
|All other Versions: 4GB
||Home Premium: 16GB
||Enterprise: 4 GB
||Business: 4 GB
||Home Premium: 4 GB
||Home Basic: 4 GB
||Starter: 1 GB
Are DDR3, DDR2 backward compatible with DDR2, DDR1?
Answer: No. DDR3 is not backward compatible with DDR2 and DDR. e.g. DDR3 has 1.5V power, DDR2 needs 1.8V and DDR needs 2.5V power and DDR3, DDR2 DIMMs come in a new 240-pin module. In terms of standard motherboard slots also the notch or the key for different memory modules is at different place for the three type of memory thus preventing any accidental insertion in memory slots which can damage the memory and or the motherboard.
Is that normal if I install 4GB memory but BIOS can only recognizing about 3.6 GB capacities?
Answer: Yes, it’s normal because when you install more than 4GB capacity, system resources (including ICH,AGP/PCI etc) will re-map memory address from upper memory area to lower area, that’s why BIOS always shows less than 4GB capacity.
Why can't my computer boot after module is inserted?
Answer: Please follow the bellow steps-
1. Please confirm the module is suitable for your computer. Cheek “Product Compatibility” section.
2. Power off the computer and re-install the module again.
3. Please try to change the order if more than one module is installed.
4. Please try to install TwinMOS module only/alone.
Why does the "out of memory" error message appear when large amounts of memory are installed?
Answer: The Windows 32-bit protected-mode cache driver (Vcache) determines the maximum cache size based on the amount of RAM that is present when Windows starts. Vcache then reserves enough memory addresses to permit it to access a cache of the maximum size so that it can increase the cache to that size if needed. These addresses are allocated in a range of virtual addresses (3 to 4 gigabytes) known as the system arena.
On computers with large amounts of RAM, the maximum cache size can be large enough that Vcache consumes all of the addresses in the system arena, leaving no virtual memory addresses available for other functions, such as opening an MS-DOS prompt (creating a new virtual machine). To work around this problem, use the MaxFileCache setting in the System.ini file to reduce the maximum amount of memory that Vcache uses to 512 megabytes (524,288 KB) or less.
This issue would occur under Microsoft Windows 95/98/98SE/Me.
You may refer to below url for solution.
Why storage capacity of the product slightly less than it written on the product specification?
Answer: All storage product will display a lower than stated memory capacity when they are viewed on a computer. The reason for this discrepancy is the way in which Flash memory and Hard drive manufacturers calculate a megabyte of memory.
Windows calculates a megabyte, or 1,000KBs (or 1,000x1,000 bytes), as 1,000KBs, when in fact the correct calculation is 1,024KBs. So, for a 512MB storage device, Windows will calculate it as having a capacity of 512,000,000÷1,024÷1,024=488, 281,250 bytes or 488.28MB. In addition it has a memory capacity overhead of between 1 – 3% to allow for:
b. Software applications
c. Enhanced data storage reliability
So, when everything is taken into consideration, your product displaying a lower than specified memory capacity is in fact normal.
Where I will get the Application Software for my USB flash drive?
for your TwinMOS USB Flash Drives, we have all kinds of Application software in our web site’s Download section. Please visit for you appropriate Application software.
My computer does not detect USB flash drive.
Answer: Please follow the steps below to diagnose the problem.
Step 1: Verify the function of USB Flash drive (UFD)
1-1. If you have connected the UFD through extension cable, HUB or front USB port, please try to connect it to your PC USB port directly.
1-2. Verify the function of UFD with other PC platform if possible. If the UFD does not response to any PC you’ve tried, the UFD might be malfunction, please return it for the warranty service.
Step2: Check if UFD is installed correctly on your PC system.
If the UFD works without problem on other PC platform, please check if it is installed properly on your PC system.
2-1. Go to Start—Settings—System—Device Manager
2-2. Go to Universal Serial Bus controllers and look for an attached device but is labeled with an “exclamation, question or X mark”. Once found, please uninstall this device.
2-3. Also uninstall the Universal Serial Bus controller that has USB mass storage device listed under it!
2-4. Unplug the USB flash drive
2-5. Restart your computer
2-6. Once the system has properly booted, plug-in your USB flash drive
2-7. Your computer should automatically detect new hardware and a “Removable Disk” should appear in “My Computer”.
What is different between USB2.0 and USB3.0? My computer only has USB 2.0 ports; can I use the USB 3.0 USB Flash Drive?
Answer: Compared USB3.0 with USB2.0, USB3.0 has high transfer rate and stronger power supply. The highest transfer rate of USB3.0 is 4.8 Gbps and the power supply is 900mA whereas the transfer rate of USB2.0 is 480 Mbps and power supply is 500mA. So, USB3.0 transfer rate is ten times the USB2.0 and supply stronger power. USB3.0 is backward compatibility with USB2.0. But if USB 2.0 device is connected to USB3.0 port, it will only operate at USB 2.0 transfer rate.
What does ready boost do? Is my TwinMOS Flash Drive support ReadyBoost?
Answer: ReadyBoost is a component of Microsoft Windows, first introduced with Microsoft's Windows Vista and also included with Windows 7. It works by using flash memory, a USB pen drive, SD card, CompactFlash, external hard drive or any kind of portable flash mass storage system as a drive for disk cache in order to accelerate the system. Yes, every models of TwinMOS USB Flash Drive support ReadyBoost and it is 100% compatible.
What is the SD Card Speed Class?
Answer: The SD Association has established specifications that rate the minimum data transfer in SD, SDHC, SDXC, SDHC UHS-I and SDXC UHS-I memory cards and host products. The speed rate specifications were established based on the needs of movie and video companies. Video recording requires certain writing speeds when recording the data onto an SD card. The SD Speed Class and UHS Speed Class standardized the specification for both card and host devices in order to guarantee minimum writing speeds.
What are the applications for Speed Class?
Answer: The Application of Speed Class are given bellow-
Class 2 : H.264 video recording, MPEG-4, MPEG-2 video recording
Class 4: MEPG-2 (HDTV) video recording, DSC consecutive shooting
Class 6: Mega-pixel DSC consecutive shooting, professional video camera
Class 10: Full HD video recording, HD still consecutive shooting.
What does "X"-speed rating means?
Answer: The "X" speed rating gives users a performance indicator on how fast the card can transfer images. Flash cards with higher speed rating X-speed rating are designed to perform faster. The X-speed rating can also be translated into another common measurement of performance - MegaBytes (MB) per second of read speed. To determine the actual MB per second, you must know the value of "X" and do the math using the multiplier number and the value of X as claimed by the product. For example: Value of X = 150 KiloBytes* per second, noted as 150 KB/sec. So, 133X = 133(multiplier) x 150KB/sec or 20 MB/sec 1 KB = 1,000 Bytes; 1 MB = 1 million BytesNote: The speed may vary due to host and device configuration.
What is the CPRM? Is CPRM applied to all data types stored on the SD card?
Answer: CPRM - Content Protection for Recordable Media - provides the method of copyright protection for SD-Audio and SD Binding technology. No, copy-protection is not mandatory for all data types and can be asserted selectively at the discretion of the content owner. CPRM technology, a copy protection mechanism, is embedded in all SD cards and can be used to protect copyrighted content such as most commercially distributed music and movie files. To use CPRM with SD cards, CPRM compliant products such as SD-Audio players, SD-Video mobile phones or enabled devices such as a PC with CPRM enabled SD slot or CPRM enabled USB read/write are also required.
How a solid state disk [SSD] works so fast?
Answer: SSD have lower access time and latency also seek latency in an SSD is close to zero. A SSD has zero rotational latency and can maximize I/O data transfer performance immediately after I/O is requested. TwinMOS SSD used NAND based Flash memory & no moving parts which can be access instantly which is very faster than any traditional HDD.
Should I defragment the TwinMOS SSD to maintain optimal performance?
Answer: There is some basic difference between SSD and traditional HDD. With Solid State Drives (SSD) becoming a popular storage solution in today’s computers, it’s important to understand the differences between SSD and Hard Disk Drives (HDD). Defragmentation describes the process of physically organizing the contents of an HDD or partition so that the data sectors of each file is stored close together to reduce load and seek times. However, SSDs can randomly access any location on the drive and are designed to write data evenly across all sectors. Nonetheless, each sector of an SSD has a limited number of writes before it can no longer be overwritten. And even though this theoretical limit cannot be reached in today’s work environment, defragmentation causes unnecessary write processes and/or wear to the SSD, directly affecting SSDs write limits. Finally, defragmentation is a safe option; it is neither necessary nor recommended for SSD.
Can I use the TwinMOS Portable HDD as a bootable device?
Answer: Portable HDD’s main function is for using as a removable storage device via USB interface but If you would like to boot from your portable HDD, please note the following matters:
Please check if your computer supports bootable USB functions, and the portable HDD can be detected upon booting. Also, please check that the software installed can support booting from USB devices. If the Portable HDD cannot be detected upon booting, then your computer does not support booting from Portable HDD.
How can I make several Partitions on my Portable HDD and SSD?
Answer: By default there is only one unallocated drive but if you want to make several partitions then please follow the bellow steps-
a. From desktop or from start button right click on “my computer”.
b. Select “Manage”.
c. Then select “Disk Management”.
d. You can see one “Unallocated Disk” right click on that and select “New Simple Volume” & follow the instructions.
e. If you want to make two different [you can choose more] partitions then select your desired capacity for each volume and format each drives.
f. In your “my computer” you can see “New Volume” or “Local Disk” [Generally] new partitions.
Why my Portable HDD is not detecting/working with all Computers?
Answer: If your TwinMOS Portable HDD working with some computer and not working with another then please follow the bellow steps-
a. Remove USB extension cable; try to connect directly to the PC or laptop main board’s USB port.
b. Do not use long USB cable; always use our supplied Y shape USB cable.
c. If it’s not detected by your system and making small sound [tick tick] its mean Portable HDD didn’t get proper power, please insert both USB connector [Y-shape cable] to your system and another connector to the Portable HDD. Now, It should work fine with any system.
Why sometimes TwinMOS SSD called combo SSD?
Answer: TwinMOS has two different series of SSD; one is Combo series SSD and another is performance series SSD. Actually combo SSD can work with laptop as internal HDD and as a external portable HDD, that’s why this series often called combo SSD. There is one USB mini port for external use as a Portable HDD and one SATAII connector to use internal as well as.
What is the maximum speed for USB3.0 PCI-e/Express Card?
Answer: TwinMOS USB3.0 PCI-e/Express Card support theoretically maximum SuperSpeed up to 5Gbps but in practical field, due to the variation of hardware and operating system platform it may differ. To get the higher performance you should connect the power socket and should use best quality & small length of USB3.0 cables. Speed may also vary with the device performance also. To get optimal performance please read the PCI-e installation guide.
What is the difference between TwinMOS All in one card reader with Combo Gadget?
Answer: TwinMOS has all in one card reader which can read and write all kinds of Flash Cards/Memory Cards. TwinMOS has newly launched another innovative product name as Combo Gadget which support three USB2.0 HUB and all in one card reader/writer as well as, for this reason this device is called Combo Gadget. It’s super compact combination of USB HUB and All in one card reader.
What is HDDokerz and how it works?
Answer: This is one kind of HDD accessing device, which makes the data copy more easier than ever. This is another innovation of TwinMOS for that peoples who are always trying to share huge amount of data in a very short time like- large HD files, Multimedia files, Movies, Music, Data backup, HDD cloning etc. It is very suitable home user also just put your HDD and you will be able to access your data with SuperSpeed USB3.0 Interface which support up to 5Gbps. Just put your 2.5” or 3.5” HDD and share with SuperSpeed interface.
What is EzeeHUB and what is the benefit of this?
Answer: TwinMOS has three different models of USB HUB which is name is EzeeHUB. It has 4ports, 7ports and 10ports of high speed USB2.0 interface. Now a day’s USB based device is increasing due to its compatibility and easy access but our computer has limited number of USB ports for this reason we often need extra USB HUB. TwinMOS high speed EzeeHUB is more compact and attractive design with different color to choose. EzeeHUB has the facility to use with and without adapter. In the case of power hunger device you need to use adapter otherwise and most of the case you can use this device without adapter but we always recommend using adapter.
I just bought a digital camera. Why should I buy a flash card reader?
Answer: Generally, your digital camera connects to your computer through a USB or serial port, but this can be inconvenient. A flash card reader attaches to your PC's USB port and transfers with high speed data between your digital camera and your computer without the need to connect the camera itself to the computer. You can transfer data even when you don't have your camera with you and, unless you have an AC adapter for your camera, downloading files from your camera to your computer can be a serious drain on your batteries. A flash card reader conserves the battery life of your digital camera or other digital device. So, if you consider all the things then it’s better to use one card reader for better performance and durability of the Flash card.