SanDisk microSD 16 GB lelong at Amazon for only $10.35.....dirt cheap!

BusNo64

BusNo64

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SLS selling at abt S$26....Amazon lelong for only USD10.35....i hoot 30 pcs juz now for myself, sis, frens and colleagues.... dirt cheap....:D

http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias=aps&field-keywords=micro+sd+16+gb&x=0&y=0

41X6fJ0fIXL._AA115_.jpg
 
BusNo64 said:
SLS selling at abt S$26....Amazon lelong for only USD10.35....i hoot 30 pcs juz now for myself, sis, frens and colleagues.... dirt cheap....:D

http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias=aps&field-keywords=micro+sd+16+gb&x=0&y=0

41X6fJ0fIXL._AA115_.jpg
Click to expand...

Price depends on speed R/W MB/S also not just the capacity. Must compare carefully.
Some slow cards slow down my phone until I fed up changed it. SanDisk got at least 4 different speed SD cards.

Top speed card is 30MB/s costing US$219
http://sandisk.com/products/mobile1-memory-products/sandisk-ultra-microsdxc-card

Slow cards may by only 4MB/s

That is not even the slowest, I read online that some cards are 2.XMB/s only.
 
uncleyap said:
Price depends on speed R/W MB/S also not just the capacity. Must compare carefully.
Some slow cards slow down my phone until I fed up changed it. SanDisk got at least 4 different speed SD cards.

Top speed card is 30MB/s costing US$219
http://sandisk.com/products/mobile1-memory-products/sandisk-ultra-microsdxc-card

Slow cards may by only 4MB/s

That is not even the slowest, I read online that some cards are 2.XMB/s only.
Click to expand...

Shit my Sony micro SD card is min 4Mb/s. So if I put that on my mobile, it will slow it down?
 
Last edited:
tonychat said:
Shit my Sony micro SD card is min 4Mb/s. So if I put that on my mobile, it will slow it down?
Click to expand...

Today's smart phones scan SD card up and down for TOO many Kah-Poh businesses. And unlike huge memory PC / Laptops that have big RAM to cache the slower devices, phones & tablets are with tiny amount of RAM. So even if you are just scanning the same locations 1000X over, it is not taken from RAM cache, but physically read slowly from the slow devices like 4MB/S cards.:(

That usually is your games / music / video / email / web etc.

The honest store selling flash memory devices state prices against their speeds. So check carefully or check Internet before you pay for these.

http://en.wikipedia.org/wiki/Secure_Digital

Transfer modes

Various SD cards may support various combinations of the following bus types and transfer modes. The SPI bus and one-bit SD bus are mandatory for all SD families, as explained in the next section.

SPI: Serial Peripheral Interface Bus is primarily used by embedded microcontrollers. This bus type supports only a 3.3-volt interface.
One-bit SD: Separate command and data channels and a proprietary transfer format.
Four-bit SD: Uses extra pins plus some reassigned pins. UHS-I and UHS-II requires this bus type but after the card is reconfigured to communicate at 1.8 volts.
UHS-I: Some SDHC and SDXC cards support Ultra High Speed mode,[16] in which the maximum data transfer rate is 104 MB/s, a quadrupling of the original top rate of 25 MB/s. UHS bus interfaces are backward compatible. SDXC UHS-I and SDHC UHS-I memory cards can achieve best performance when paired with a UHS-I device and are designed to let consumers record HD resolution videos to tapeless camcorders, plus perform other simultaneous recording functions.
UHS-II: Available exclusively on SDHC and SDXC products. The standard further raises the data transfer rate to a theoretical maximum of 312 MB/s.[17]

[edit]
Click to expand...


Speeds

An SD card's speed is measured by how quickly an amount of information can be read from, or written to, the card. In applications that require sustained write throughput, such as video recording, the device might not perform satisfactorily if the SD card's class rating falls below a particular speed. For example, a camcorder built for a Class 6 card may suffer dropouts or corrupted video if a slower card is used. Digital cameras may experience a noticeable lag between shots, while the camera writes the picture to a slower card.

A card's speed depends on many factors, such as the following:

The likelihood of soft errors that the card's controller must re-try
The fact that, on most cards, writing data requires the controller to read and erase a larger region, then rewrite that entire region with the desired part changed
The possibility of fragmentation: that a body of information the host views as a unit is, for historical reasons, written to non-contiguous regions of memory. (This possibility does not cause rotational or head-movement delays as with magnetic media, but it does vary the amount of computation the card's controller must do.)

In early SD cards, the speed was measured with the × rating, which compared the average speed of reading data to that of the original CD-ROM drive. Currently, the official unit of measurement is the Speed Class Rating, which guarantees a minimum rate at which data can be written to the card.

The newer families of SD card improve card speed by increasing the bus rate (the frequency of the clock signal that strobes information into and out of the card). Whatever the bus rate, the card can signal to the host that it is "busy" until a read or a write operation is complete. Compliance with a higher speed rating is a guarantee that the card limits its use of the "busy" indication.
[edit] Speed Class Rating
32GB SDHC card

The Speed Class Rating is the official unit of speed measurement for SD cards. The class number guarantees a minimum write speed as a multiple of 8 Mbit/s (1 MB/s). The SD Association defines several speed class ratings, but manufacturers may claim conformance to those ratings without independent verification.

Unlike the earlier "×" speed ratings, the host device can read a card's speed class. A device can warn the user if the card reports a speed class that falls below an application's minimum need.[25]

These are the ratings of all currently available cards:[14][26]

Class Speed
SDHC Speed Class 2.svg Class 2 2 MB/s
SDHC Speed Class 4.svg Class 4 4 MB/s
SDHC Speed Class 6.svg Class 6 6 MB/s
SDHC Speed Class 10.svg Class 10 10 MB/s

Speed Classes 2, 4, and 6 assert that the card supports the respective number of MB/s as a minimum sustained write speed for a card in a fragmented state. Class 10 asserts that the card supports 10 MB/s as a minimum non-fragmented sequential write speed.[25] By comparison, the older "×" rating measured maximum speed under ideal conditions, and was vague as to whether this was read speed or write speed.

Recent developments

On 21 May 2009, Panasonic announced new class 10 SDHC cards, claiming that this new class is "part of SD Card Specification Ver.3.0".[27] Toshiba also announced cards based on the new 3.0 spec.[28]

On 1 June 2010, Pretec announced the new Class-16 HD-video grade SDXC 64 GB card at Computex Taipei 2010.[29]


[edit] UHS Speed Class

Requiring a new bus, the UHS Speed Class is intended for use in applications like real-time broadcasts and capturing large HD videos. The only currently available UHS SD cards are UHS Speed class 1.[31]
Click to expand...


<p>The × rating is a multiple of the standard <a href="/wiki/CD-ROM" title="CD-ROM">CD-ROM</a> drive speed of 1.2*<a href="/wiki/Mbit/s" title="Mbit/s" class="mw-redirect">Mbit/s</a> (approximately 150*<a href="/wiki/KB/s" title="KB/s" class="mw-redirect">kB/s</a>). Basic cards transfer data up to six times (6×) the CD-ROM speed; that is, 7.2 Mbit/s. The 2.0 specification defines speeds up to 200×, but is not as specific as Speed Classes are on how to measure speed. Manufacturers may report best-case speeds and may report the card's fastest read speed, which is typically faster than the write speed. Vendors including <a href="/wiki/Transcend_Information" title="Transcend Information">Transcend</a> and <a href="/wiki/Kingston_Technology" title="Kingston Technology">Kingston</a> report their cards' write speed.<sup id="cite_ref-29" class="reference"></p>

<p>This table lists common ratings, the minimum transfer rates, and the corresponding Speed Class (though the comparison is not always exact).</p>
<table class="wikitable">
<tr>
<th valign="top">Rating</th>
<th valign="top">Read Speed<br />
(Mbit/s)</th>
<th valign="top">Read Speed<br />

(MB/s)</th>
<th valign="top">Write Speed<br />
(Mbit/s)</th>
<th valign="top">Write Speed<br />
(MB/s)</th>
<th valign="top">Speed<br />
Class</th>
</tr>
<tr style="text-align:right;">
<td>6×</td>

<td>7.2</td>
<td>0.9</td>
<td></td>
<td></td>
<td></td>
</tr>
<tr style="text-align:right;">
<td>10×</td>
<td>12.0</td>
<td>1.5</td>
<td></td>
<td></td>

<td></td>
</tr>
<tr style="text-align:right;">
<td><b>13×</b></td>
<td><b>16.0</b></td>
<td><b>2.0</b></td>
<td><b>16.0</b></td>
<td><b>2.0</b></td>
<td><b>2</b></td>
</tr>
<tr style="text-align:right;">

<td><b>26×</b></td>
<td><b>33.0</b></td>
<td><b>4.0</b></td>
<td><b>32.0</b></td>
<td><b>4.0</b></td>
<td><b>4</b></td>
</tr>
<tr style="text-align:right;">
<td>32×</td>
<td>38.4</td>

<td>4.8</td>
<td>40.0</td>
<td>5.0</td>
<td></td>
</tr>
<tr style="text-align:right;">
<td><b>40×</b></td>
<td><b>48.0</b></td>
<td><b>6.0</b></td>
<td><b>48.0</b></td>

<td><b>6.0</b></td>
<td><b>6</b></td>
</tr>
<tr style="text-align:right;">
<td><b>66×</b></td>
<td><b>80.0</b></td>
<td><b>10.0</b></td>
<td><b>80.0</b></td>
<td><b>10.0</b></td>
<td><b>10</b></td>

</tr>
<tr style="text-align:right;">
<td>100×</td>
<td>120.0</td>
<td>15.0</td>
<td>120.0</td>
<td>15.0</td>
<td></td>
</tr>
<tr style="text-align:right;">
<td>133×</td>

<td>160.0</td>
<td>20.0</td>
<td>160.0</td>
<td>20.0</td>
<td></td>
</tr>
<tr style="text-align:right;">
<td>150×</td>
<td>180.0</td>
<td>22.5</td>

<td>180.0</td>
<td>22.5</td>
<td></td>
</tr>
<tr style="text-align:right;">
<td>200×</td>
<td>240.0</td>
<td>30.0</td>
<td>240.0</td>
<td>30.0</td>

<td></td>
</tr>
<tr style="text-align:right;">
<td>266×</td>
<td>320.0</td>
<td>40.0</td>
<td>320.0</td>
<td>40.0</td>
<td></td>
</tr>
<tr style="text-align:right;">
<td>300×</td>

<td>360.0</td>
<td>45.0</td>
<td>360.0</td>
<td>45.0</td>
<td></td>
</tr>
<tr style="text-align:right;">
<td>400×</td>
<td>480.0</td>
<td>60.0</td>

<td>480.0</td>
<td>60.0</td>
<td></td>
</tr>
<tr style="text-align:right;">
<td>600×</td>
<td>720.0</td>
<td>90.0</td>
<td>720.0</td>
<td>90.0</td>

<td></td>
</tr>
</table>
Click to expand...
 
Last edited:
uncleyap said:
Today's smart phones scan SD card up and down for TOO many Kah-Poh businesses. And unlike huge memory PC / Laptops that have big RAM to cache the slower devices, phones & tablets are with tiny amount of RAM. So even if you are just scanning the same locations 1000X over, it is not taken from RAM cache, but physically read slowly from the slow devices like 4MB/S cards.:(

That usually is your games / music / video / email / web etc.

The honest store selling flash memory devices state prices against their speeds. So check carefully or check Internet before you pay for these.
Click to expand...

Thks Yap, appreciate the info ..:)

What speed level do you suggest for micro sd that is for mobile? 30mb/s?
 
SLS mark up price by 300% profit. Actual cost is only $6 for 16GB is buy bulk 100pcs. If buy in China 32GB only S$20 for one pcs celling in shop.
 
tonychat said:
Thks Yap, appreciate the info ..:)

What speed level do you suggest for micro sd that is for mobile? 30mb/s?
Click to expand...

I think there is a ladder of speed+capacity relation tied. Don't use very big capacity card that is very slow. That will frastrate you like hell making you wait. Buy higher speed (& $$) when you need higher capacity. You may on the other hand find not much different to use a low speed card when you use say only 1G or 2G capacity. I wanted to say 512MB - but don't think they are available for sale any more, but I do have 3pcs of 256MB & 1 pc of 512MB left around in old phones.

RAM is lower cost already, I hope phone makers add more RAM, then cache up the slow flash devices. As it is, there are very little RAM in smart phones, and unlike PC they don't even have swap. Swap using HDD is already slow, but necessary when RAM cost were sky high.

S$30 can get 4GB of DDR3 today.;)
 
uncleyap said:
Price depends on speed R/W MB/S also not just the capacity. Must compare carefully.
Some slow cards slow down my phone until I fed up changed it. SanDisk got at least 4 different speed SD cards.
That is not even the slowest, I read online that some cards are 2.XMB/s only.
Click to expand...

aiya uncle, i am using 2mb for my smartphone and tablet.....okay lah....of coz slowly den 6 or 10mb...but for dat price, cannot hiam too much lah....store doc, music or movie...work without problem..swee swee....for games better to store internally...so far so good lah...
 
BusNo64 said:
aiya uncle, i am using 2mb for my smartphone and tablet.....okay lah....of coz slowly den 6 or 10mb...but for dat price, cannot hiam too much lah....store doc, music or movie...work without problem..swee swee....for games better to store internally...so far so good lah...
Click to expand...

If the speed you found acceptable means OK loh.

:) I have found some phones do scanning of music & video to the playlist. Sluggish like hell. Camera and less Kay-Poh devices may tolerate slow cards better. But be-careful of HDTV camera recording video they may demand speed of the card. ;)
 
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