NVidia cards require that you install the CUDA drivers in addition to the standard video card drivers (ATI/AMD cards ship with OpenCL as part of their driver package). Without these drivers installed they will not be available to any miners.
Since the Quadro 600 appears on the list of CUDA compatible GPUs it should be mineable, though what kind of ...
I'm surprised you just didn't ask me directly.
It sounds a lot like you're suffering from one of two CPU use bugs in the driver. Catalyst 11.7 through 11.11 (using any SDK) use 100% CPU time on one or more cores because of a faulty sleep, and SDK 2.2 and 2.3 (using any Catalyst) also have the same exact issue.
However, Windows has a third variation of the ...
One of your CPUs is spin-waiting for the GPU to finish work units. Generally, GPU drivers have two options to wait for the hardware: either suspend the process until an interrupt is generated, or poll the GPU whether it is finished in a tight loop. It seems your driver is using the second approach and thus takes 100% CPU of one core.
The advantage of ...
It almost certainly is related to the question you linked and it almost certainly has the same answer I'm sad to say. There is a lot of this going around and no one is really certain what exactly is causing it.
There have been reports that ATI's 11-7_vista64_win7_64_dd_ccc_ocl drivers often bring the problem about, and reverting back to an 11-6 version ...
Make sure That you have, in your bitcoin.conf file located in ~/Library/Application Support/Bitcoin at least the following:
Restart Bitcoin client, enjoy Bitcoin solo mining. ;)
The BitMinter miner also works on Mac OS X. Go to http://bitminter.com and click the "engine start" button. There's no installation, it starts from the browser. It requires Java.
As to what is going wrong with DiabloMiner, I don't know. If it is mining without errors then it should be getting you shares at the pool.
It's hosted at github.
Downloads are here.
It's open source, so you can check the code to see how safe it is.
There's an old but still active thread on the bitcointalk forums.
It looks like the program is java code and so doesn't need compiling for OSX, and also that there's a script DiabloMiner-OSX.sh that runs it on OSX.
Correct locations might be either ~/Library/Application Support/Diablominer or ~/.diablominer
Of course it might be in in an incorrect location. Super Meat Boy, for instance, stores its configuration inside the .app itself (brrr). To check there you have to right click the app and "show package contents".
The best way to find this configuration file, if ...