at first, the problem was manageable - the dots rarely obscured what i was reading and the machine never crashed. i wasn't sure if the problem was hardware or something that ubuntu was doing, so i lived with it and in some ways even liked it, in a "ghost in the machine" sort of way. but over the next year the problem got somewhat worse and at this point the problem had persisted thru several ubuntu versions (including a clean reinstall that i'd done for the sake of seeing if some configuration change i'd made was part of the problem), so i was forced to track down the cause
i "live chatted" with intel support and they told me to run the intel processor diagnostic tool. the standard tool is windows-only, but they include a link to a fedora15-based liveUSB version. the instructions seemed cryptic to me, the utilities were ".exe"s, possibly directed to windows users (though why they wouldn't just use the standard tool ???) and the intel support team stated:
Alberto: the thing is that we are not that familiar with Linux
so they were useless. tl;dr - it took me (much) longer than it should have to run the tool. but eventually i got it running, the "snow" still appeared (ie, the fedora15 system exhibited the glitch), but the tool reported that all tests passed, ie the tool was useless (it didn't verify that the generated images matched the desired values). fwiw, here's the easiest way i found to use the tool:
- download the iso (eg, this one)
- i'll call it ipdt.iso for simplicity
- insert a usb drive (i'll call this /dev/sdX)
- we're going to overwrite the drive, so *all data* on it will be lost
- if it automounts, unmount it
- in my case, it was recognized as /dev/sdd
- dd bs=4M if=ipdt.iso of=/dev/sdX
- insert the usb drive into the target computer and boot from it
- most modern systems support boot-from-usb. if yours doesn't, maybe you could burn a cdrom ???
- fedora should boot up
- open up a terminal and type (for a 64bit system)
- click the "ipdt" icon on the desktop
next, intel suggested i swap CPUs between the 2 systems. i did this and the problem (ie the "snow") followed the 3220. the 2105 CPU showed zero symptoms in either machine. at this point, intel agreed that the CPU was probably faulty and they've presented me with two warranty options
- Standard Warranty Replacement: This is when you send the processor first to us, and then once we receive it, it takes 5-8 business days for you to receive the replacement processor.
- Advance Warranty Replacement: This is when we send you the processor first, and then, once you receive it you just need to send your defective processor back to us. There is a fee on this option, $25, not refundable, that covers the overnight shipment of the processor to you, and also it covers the shipping for you to send the defective processor back to us. And also for security reasons, we are going to charge the price of the processor to your credit card, just in the meantime, as soon as we get your defective processor we will do a refund for that amount.
those are both pretty horrible options. this is *intel's* poor workmanship resulting in me living with a minor annoyance for over a year, ultimately forcing me to spend 2 work days tracking down the problem, their diagnostic tool failed to detect *any problem*, and now they want me to pay $25 to replace it or else live without a working computer for on the order of 2 weeks. pretty ridiculous
grrr intel. but whatever. they're a monopoly and i don't have much choice. maybe next upgrade cycle i'll go back to AMD (if intel hasn't driven them to bankruptcy yet). i submitted the serial number they requested and am waiting on shipping info