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Disclaimer

I am not responsible for any data loss, broken hardware, lost hardware, costs made, or other things that happen to you/your goods because you did what I did. All that is written on this website, worked for me, and is certainly not guaranteed to work for anybody else. Therefore, you are always responsible for what you do. Of course, you are encouraged to post your experiences as a comment to the related post. :-)

Cache

What?!

A cache is a piece of storage that is used to reduce the performance impact that a bottleneck can have on your system.

Why cache?

For example, the cache of a processor(CPU) is a small piece of memory, size varying between less than a megabyte to several MB’s, in which frequently accessed data is stored, so that it doesn’t have to be loaded from the relatively slow RAM. That’s how “caching”  reduces the data that needs to be transmitted and received, so that more bandwidth is available for other operations.

Another example of caching is the cache in a hard drive(HDD). This is usually a somewhat bigger cache(about 32 to 64MB on newer drives). The cache is used as a sort of buffer, where several small write-operations can be stored before being written to the HDD, so that the OS can continue with other things, and the HDD can stay at a constant(slower) write speed. Also, while the data is in the cache, the HDD can arrange them in an optimal order to improve write speeds(check out AHCI). This is called Native Command Queuing(NCQ).

Yeah… So?

So, caching speeds up your system, because devices don’t have to wait for each other to finnish a task, thanks to the small but fast piece of memory called cache.

Be careful though. Cache’s are usually volatile memory. Which means, that when the power fails, all data stored in it is lost. This can be tricky with big HDD caches. You think a piece of data is already written to the HDD, but in fact it’s still in the cache, waiting in the queue.

Bottleneck

What?!

“Bottleneck” is a name for any device or interconnect between devices, that has “the slower speed”, thus reducing the speed with which other devices, connected to this “bottleneck” are able to do their thing.

Why “bottleneck”?

See this image? Looks a little like the neck of a bottle doesn’t it? Imagine that one device, call it “top-half”, wants to send data to another device, which we call “bottom-half”. To do so, it needs to send the data through a port, bus, interface, device, connection, whatever you want to call it. We’ll call it “the pipe”.

Oh, this is embarassing, a missing picture....

You can see, that no matter how much data top-half has, it will only reach bottom-half with the speed, or bandwidth, or gigatransfers of the pipe. So no matter how many Ghz, Gflops, or terabytes the top-half can crunch, it will only send data to the bottom-half at the speed op the pipe, so the bottom-half can only operate at the speed of the pipe, because it simply doesn’t get any more data to process. This is called a “bottleneck”.

So in short, slow RAM isn’t optimal since it can handle less data throughput, a mind-boggling CPU will sit idle for most of the time if the other components and interconnects are slow, and there’s little use in getting a fast SSD if your motherboard can’t handle the speed.

Yeah… So?

So, the more bottlenecks you find and remove out of your system, the faster it gets. This is one of the magic things that makes the difference between just spending a lot of money, and building a good PC.

Reset Macbook Pro LED backlight: solve dark bands on the screen

Reset Macbook Pro LED backlight

Here is the magic key command to reset Macbook Pro Led Backlight:

ctrl-shift-eject

You can use this key command to (temporary) fix the problem of dark bands showing on the screen.  Note that the screen will go black, just press any key to wake it up again.

I had this problem, and it took me a while to find out I didn’t have to replace the led inverter board, but could just hit this key command every now and then when the problem’s there.

Here’s a link to the official Apple page.

All-In-One (AIO) thin mini-ITX cases

Before I give you the list of cases I’ve found, I’ll first explain a little about the thin Mini-ITX form factor.

Thin Mini-ITX form factor

In a nutshell, thin Mini-ITX is a form factor that is almost the same as the normal mini-ITX form factor. The difference, as the name suggests, is in the height. Thin Mini-ITX motherboards are limited to a maximum height of 20mm, compared to 57mm for normal Mini-ITX boards. This makes them very suitable for All-In-One(AIO) desktop systems.

If you want more than a nutshell, here is a link to the document with all the specifications for Mini-ITX and thin Mini-ITX.

So, here’s a little list of the thin Mini-ITX form factor All-In-One cases I’ve found so far.

CTL All-In-One 650T Touch screen

There’s the CTL’s All-In-One 650T Barebone chassis with touchscreen @ ctlcorp.com. It’s a little hard to find information about it, so ïll just be linking to the original website. Here’s the non-barebone version @ ctl.net. One youtube I found this video where a guy from CTL opens the thing up and shows you around a bit.

Advantages:

  • Touch screen.
  • It’s hard to name more advantages, because there’s so little information around. I can’t even tell you if it’s Full-HD or not(although I expect it to be).

Disadvantages:

  • No information on their website, which makes me wonder if this is the case I’d need.
  • Only 65 TDP CPU’s
  • Integrated graphics only

Loop LP-2150 All-In-One PC

The Loop LP-2150 seems to be a very popular thin Mini-ITX case, and almost the only All-In-One desktop solution(except the above CTL 650T). Tom’s Hardware made their own AIO PC using the Loop LP-2150 chassis: http://www.tomshardware.com/picturestory/604-do-it-yourself-all-in-one-thin-mini-itx.html Continue reading All-In-One (AIO) thin mini-ITX cases