Yesterday it was finally delivered! That's Dell XPS 9100, Intel i7-930, 2.8 GHz, 12 GB RAM, 1TB HDD, ATI Radeon HD5670. Here it is:
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This thing is big and heavy! The box, which it came in, was huge! The Purolator guy who delivered it was driving a full size truck, which he backed up to our driveway, and took it all. Normally he drives a regular post office delivery vehicle, but not this time. I guess the big truck was chosen just because of my box. :)
So, I got the new PC set up and running, got Ubuntu installed, copied most important stuff from the old PC, set up Mozilla environment, and tried the build. It took about 20 minutes! A huge improvement compared to the old PC! Now I can build even during the work day, not overnight, as I usually did before.
By the way, it took me a while to install Ubuntu. I wanted 32 bit version, as it's known to have less compatibility issues, but its installation was consistently failing somewhere in the middle. I burned three CDs on two different CD-writers, tried USB-drive - no luck. Only the alternative (text-based) setup worked, though it was very slow. But after I finally installed and ran the system I realized, that 32 bit limits the available RAM to 4GB. Somehow I forgot about that, or rather just didn't think that Linux has the same limitations as Windows (why would it be different?). I just didn't use 64 bit system, and didn't have more than 4GB of RAM in my PC before, so my unconscious mind didn't tell anything. Anyway, I installed the amd64 version, got access to total 12GB of RAM, and now I'm all set.