Overhead on memory sticks?

Apr 04, 2007 42 Replies

Just curious: Got a USB memory stick 4-pack at CostCo. Four Dane-Elec



512MB stick, great deal ($40). After plugging in the first one the laptop hard drive was crunching a lot (this laptop is used to USB sticks). Upon checking an empty stick it turns out that properties lists
514MB but only 490MB of that free.

What kind of overhead is in those sticks? If it's really >20MB, why so much?


Regards, Joerg http://www.analogconsultants.com

Maybe because 514/(1.024*1.024) = 490.2?

The filesystem has overhead. Check out this:

formatting link

Ben Jackson AD7GD http://www.ben.com/

That I understand. But it still doesn't explain why an empty stick has so much overhead. As a comparison, my oldest memory stick has a much lower overhead percentage. It's a 1GB Lexar and the overhead is only

14MB, versus 24MB on the new 512MB sticks. Looks like the new ones are more than a factor of three higher in overhead.
Regards, Joerg http://www.analogconsultants.com

But 2^19 = 524.29 :-)

Anyhow, whatever number of cells they squeezed in, if the net available space is 490MB it shouldn't be advertised as 512MB. But I am not complaining, it's enough for my purposes. Just wondering.

Regards, Joerg http://www.analogconsultants.com

Upon reading this, my mind went immediately to this:

formatting link

8-)

There's the marketing megabyte, which is 10^6 = 1000000 Then there's the 'proper' megabyte: 2^20 = 1048576

Not incidentally, 514*10^6 = 490.2*2^20.

It's not filesystem overhead. It's a matter of perspective.

robert

On a sunny day (Wed, 04 Apr 2007 23:55:29 GMT) it happened Joerg wrote in :

It is a rotten deal, a 2GB stick goes for 14,95 Euro (19.99 $ as today). Here is where I buy stuff and DVDs etc:

formatting link

:-(

The same is true of disk drives--the free space reported is that actually available for files, and excludes e.g. file system data structures and hot spare sectors. I don't know what Windows reports in Properties, though--I've given up trying to guess.

Cheers,

Phil Hobbs

Yeah, I know you can get really large sticks in singles. But these came in really nice designs and dazzling metallic colors :-)

I don't need 2GB and for $20 I'd only get one physical device. What I need them for is when I go to clients. Blue is for client A, silver is for client B etc. My old rule is to never, ever, mix that together. My wife liked these so much she wanted to have the red one. Not that she needs it but because it's pretty. Have to think about that...

Regards, Joerg http://www.analogconsultants.com

Phil Hobbs wrote in news: snipped-for-privacy@SpamMeSenseless.pergamos.net:

I just bought a 512MB "Attache" USB memory stick from CompUSA for

17.00,with a 13.00 rebate,so end cost was $5.(plus tax on $17,of course) I hate rebates,though;PITA.

Too bad CompUSA's site said the stick was usable on "W98/SE",and other similar sticks said "SE-only",so I thought it would work with my W98 1st edition system;nope. No drivers for W98FE.

-- Jim Yanik jyanik at kua.net

I don't like mail-in rebates at all. IMHO it's a stupid concept and I generally do not buy if that's the form of rebate. But I guess they bank on the hopes that some people will "forget". Plus maybe all the tourist shoppers and not-so-legal aliens who don't have a US bank account and cannot cash in those rebates.

Then I guess you'd be entitled to give it back.

Regards, Joerg http://www.analogconsultants.com

[Apologies for continuing off topic but] I've discovered that CompUSA, on at least some rebates, handles all of the processing on-line. Go to the magic web site and enter your store ID and receipt number; the rest is pretty much automatic. They still take forever to arrive in the mail, of course.

All the CompUSA stores around here are closing up shop. Even resorting to the auto lot game of hiring a kid to stand on the corner and wave a "going out of business" sign.

...Jim Thompson

| James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | America: Land of the Free, Because of the Brave

1GB is really 1024MB, right?

1024-986 = 38MB.

So it has more overhead than the 512MB stick.

I remember when I was proud of shaving off a word (two whole bytes!) from a PDP-11 subroutine!

Tim.

[snip]
[snip]

I have an OfficeMax account... they deliver for free. I have all kinds of coupons, $30 off in the store and 20% off from the web, etc.

I usually end up with really good prices from them.

...Jim Thompson

-- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | |

formatting link
| 1962 | America: Land of the Free, Because of the Brave

Not this one. Was marketed as 1G and shows 989 usable. I go by what the marketeers have promised and what the product actually delivers ;-)

My father had to do that. Automated a complete cold-rolled-steel line within 2K of RAM. Which was a lot back in the 60's. Just imagine, in Vista they recommend to provide 1G (!) just to make sure it can work at all. Lots of bloat, needs half a million times what my father and the guys needed. Pathetic.

Regards, Joerg http://www.analogconsultants.com

Disk drive megabytes (10^^6) have always been smaller than memory megabytes (2^^20).

I guess the question then becomes: is a flash stick a disk drive or a memory?

More like a drive because the PC handles it as such.

Regards, Joerg http://www.analogconsultants.com

OfficeMax and Best Buy (starting with their Canadian stores) are finally getting rid of the d*mn things.

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required