Okay, lesson learned: don't go cheap with the kid's PC, just bite the bullet and upgrade it when it's ancient. Also, the case is somewhat of a pain.
So I managed to get all the hardware - which was before in a decent mid-tower case - inside the CoolerMaster.
The coolermaster Hyper TX3 Evo wouldn't fit, so I looked for the original AMD cooler and did a fan swap. That's why you see a white Nexus over the CPU. But see below, after the front panel warning.
If you use this case, *pay attention*! You need to remove the front plastic to plug in the PSU, and i pulled a wire from the reset switch while doing that (you may see a piece of soldering iron to the right of the photo).
Obviously, this case will heat up more than a roomy mid tower. The problem wasn't the video card (Asus geforce 650) or the CPU, even with the fan swap. The problem was the ancient nvidia 730 chipset with integrated video. While in the mid tower it ran stuff like Minecraft and The Sims fairly OK. Even Guild Wars 2 was running, although it was laggy even with all details on minimum at 1280x1024.
In this case, it stays at 127 C according to SpeedFan. That's on idle/browsing. If you start any 3d application, even the Windows 7 experience index, it shuts down. Can't blame it on the 650, it does that in both cases, when I use the discrete graphics and when I remove the card and run off the integrated video. I even screwed a small fan to the chipset heatsink (gold with Asus logo in the middle of the board) and it didn't help any.
So... today I receive a Pentium G2020 with a mini ATX motherboard and new Ram for the rebuild. Should be 2x as fast as the old Athlon64 X2 (not Athlon II), make me coffee in the morning and solve world hunger. More importantly, it's a mini ATX board so I could have picked from like 3 million cases instead of just this one. Not to mention that if i worked half the time i spent troubleshooting this build I would have covered the cost of the new components and then some
Here's an image of the filled up case. It may look better with a modular PSU and less cabling, but the Seasonic G 360 isn't one:
Bigger version here: http://i42.tinypic.com/2uiw5xu.jpg
I have more assembly photos but too depressed to post now.