It has been several days but not a week since iMac 2.8 GHz Quad Core (with 27″ monitor) arrived. Personally, I don’t like Snow Leopard. So, still, I mainly use iMac 2.8 GHz Core 2 Duo (with 24″ monitor), which is now two years old.
In the last report, I emphasized that Apple Wireless Keyboard, which comes with the latest line of iMac models, is a horrible piece of junk. But let’s put that disappointment aside for now. Instead, I want to focus on iMac’s SDXC card slot in this report. Before purchasing iMac 2.8 GHz Quad Core, I really look forward to finding out how this card slot works. I use an SDHC memory card through a USB card reader/writer as a scratch disk. And my main question has been the following: Which is better? –
1. Use an SD/SDHC/SDXC memory card through a USB card reader/writer or
2. Use an SD/SDHC/SDXC memory card with the built-in card reader/writer
I can tell you that there will be no straight answer at the end of this report.
Anyway, first, I want to see which data writing process is faster, through a USB reader/writer or with the built-in card slot. So I have a brand-new SDHC memory card from Silicon Power. (See Screenshot 1.) I don’t know if it’s a good brand name. I have never heard of Silicon Power before. The USB memory card that I have is two years old. (See Screenshot 2.) Reading its user’s guide, there doesn’t seem to be any read/write speed limits. In addition, I have a disc image, whose file size is 3.15 GB. (See Screenshot 3.)
 Screenshot 1 – Source: MacHouse |
 Screenshot 2 – Source: MacHouse |
 Screenshot 3 – Source: MacHouse |
So I’m going to first copy this disc image that is sitting inside the internal hard disk drive onto the memory card through the built-in card reader/writer. Again, the SDHC card is brand-new, and I won’t even format or initialize it. After making a copy, I’ll remove the card from the computer (iMac 2.8 GHz Quad Core) physically. Then I’ll plug it in again through the USB card reader/writer. Next, I’ll rename the copied file by appending an ‘a’ to the file name so that I can copy the exactly same file onto the same memory card. As a result, I’ll have two files on the SDHC card. (See Screenshot 4.) The following is the resulting comparison.
 Screenshot 4 – Source: MacHouse |
1. Writing into SDHC card with the built-in card writer – 10 minutes 31 seconds
2. Writing into SDHC card through a USB card writer – 14 minutes 25 seconds
It’s not very surprising that data writing is faster with the built-in card writer. It’s 37% faster.
But this comparison shouldn’t convince every iMac user to always use an SD/SDHC/SDXC memory card with the built-in card reader/writer. As we discussed in the last article, one cannot just plug a memory card into the slot at any time. You must have a memory card inserted into the slot when you start up your iMac.
What if one uses Disk Utility to mount an SDHC card?
What if one inserts an SDHC card right after iMac finishes starting up?
What if one logs out and signs in and then inserts an SDHC card?
In all these three cases, your iMac with a built-in card reader would not recognize an inserted memory card. You can eject a card on the desktop with help of Disk Utility or simply by right-button-clicking on the card and choosing Eject. (See Screenshots 5-6.) But once it’s gone, you won’t be able to mount a card unless your restart your Mac. If you want to swap data between two computers, you may be better off by using a card through a USB card reader/writer. By the way, it can take iMac 2.8 GHz Quad Core about 36 seconds to come back after restart (Pressing Restart from a dialogue box that says Are you sure want to restart your computer now?)
 Screenshot 5 – Source: MacHouse |
 Screenshot 6 – Source: MacHouse |
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