I've recently bought my desktop a PNY Geforce GTX 650 TI Boost so I could play Steam games on Ubuntu. I've also bought a brand-new 500 W power supply unit because my older one wouldn't be able to handle the extra work and didn't have a PCI-e plug.

After carefully installing the hardware, I proceded to install the drivers. In order to do so, I've followed Luis Alvarado's tips from here. Baiscally, it involved installing the nvidia-325 package from the xorg-edgers PPA then running sudo nvidia-xconfig to create a new xorg.conf.

The instalation seems to have gone without errors or even warnings, and my computer was finally able to run resource-intensive games. However, every now and then the computer freezes. To better describe the problem:

1. The screen always freezes;


2. The sound usually goes into a loop (rarely it keeps runnning, indicating that only the screen had freezed);


3. There's absolutely no mouse or regular keyboard feedback. 90% of the time I have to Alt+PrtScrn+R+E+I+S+U+B my way through a restart, but sometimes not even that works;


4. It seems to occur at random intervals, usually when I'm running Steam games, but sometimes when I'm on Unity, working on spreadsheets and statistics software. What intrigues me is that sometimes it occurs even before the system boots (at the first POST screen, which presents the Geforce card). This makes me wonder whether the problem isn't actually in the hardware itself (which would be a shame, because it costed me a small fortune and I can't return it anymore).

So far, none of these has solved the issue:

1. Reinstalling the 325 driver;


2. Installing older drivers;


3. Installing nvidia-settings to see if there were any problems such as overheating (there isn't: the card runs at a comfy 45 Celsius even after extensive work);


4. Installing steam-login in an attempt to bypass any issues the card might be having with my onboard Intel graphics.

Since the problem sometimes occur during POST, I guess configuring something on my My CMOS might help. The problem is I'm kind of lost. Here's some settings I think might help (from "Advanced Chipset Features"):

1. Intel EIST: Enabled (GV3);


2. Intel XD Bit: Enabled (when disabled, force the XD feature flag to always return 0)


3. Intel VT: Enabled (when enabled, a VMM can utilize the additional HW Caps. provided by Intel Virtualization Tech)


4. Memory Hole Remapping: Enabled (allow remapping of overlapped PCI memory above the total physical memory)


5. Video Memory Size: 32MB (other options: 64MB and 128MB)


6. DVMT Mode: DVMT (other option: fixed)


7. DVMT/Fixed Memory Size: 256MB (other options: 128MB and Maximum)

My computer is plugged to a 24' LG TV through an HDMI cable, instead of a regular monitor. Could this be the source of the problem (or worsen it)? Unfortunately, I don't have a computer monitor here to test it. All I know is that even though I feel like I've already read all the "My computer is freezing" questions on Ask Ubuntu, I've run out of ideas on how to diagnose and fix the problem.