My computer has the following symptoms with no warnings (gadgets included); Works fine for an indefinite amount of time. Computer freezes (on the rare occasion quickly judders to a halt then freezes). Screen goes black (monitor in standby mode). Sound stops. Computer shuts down and restarts. On start up I'm told it didn't shut down properly and after windows has booted up I get this error; ******************************** SourceWindows 7 Pro 64bit Summary Shut down unexpectedly Date 23/07/2013 18:13 Status Report sent Problem signature Problem Event Name: BlueScreen OS Version: 6.1.7601.2.1.0.256.48 Locale ID: 2057 Extra information about the problem BCCode: 116 BCP1: FFFFFA8005ED74E0 BCP2: FFFFF880057ADE30 BCP3: 0000000000000000 BCP4: 0000000000000002 OS Version: 6_1_7601 Service Pack: 1_0 Product: 256_1 Bucket ID: X64_0x116_TdrBCR:2_Tdr:2_IMAGE_nvlddmkm.sys Server information: 5eedc44d-878f-4a0b-afef-b6fed4b1aaf4 ******************************** Backstory: I've had a custom built computer (but not overclocked etc in any way) from 2009 mostly with a 4870x2 (+custom cooler) and it's worked for a long time but must have started having problems as I swapped it with a 8800. This then succumbed to the same problem after a while (but it was from an older computer which could have damaged it so won't rely on it too much). It used to happen when I was playing a game then start playing Windows Media Player so used itunes. About a month ago the problem became so bad just using the internet caused it to crash or loading a game but on other occasions I could have 3 versions of the game playing no problem, there never seemed to be a pattern. It then happened every time I tried to load a game. In the end all the evidence pointed to the GPU so bought a new cheap stock 620 on a clean computer. This has worked fine for 1 month but that too is now showing the same problems although not as frequently it seems. I've got gadgets which check my CPU and only once did it warn me it had hit 82 degC then shut down (this rarely happens). My GPU has been no higher than 69 degC and when my computer's crashed the last few times it's been around 56 degC. I've now had it crash twice in close succession whereby I had 3 copies of a game running in low settings (2nd time it happened the 2 copies I wasn't active in were CPU limited and was ~60 degC). I alt tabbed between all 3 game copies to try and test the load and after a few minutes it crashed at 56 degC. The GPU fan speed was constant at 65%, load was 99% and memory used no higher than 700Mb/1Gb. I'm not entirely sure the GPU is the culprit and could be the RAM or motherboard (one place suggest maybe even the sound card but I don't know if they were talking integrated which mine isn't). Reading around suggests it can't be the CPU because my computer wouldn't work at all. What checks I could think of show no problems and given that my computer worked fine for 1 month after terminal problems suggests it is the card and I'm just unlucky or expecting too much from a cheap card especially given the prompt failures under testing. I'd appreciate any help although I'm aware that this sort of problem is particularly hard to solve and spent a lot of time trying to resolve it myself. I'll do my best to answer any further questions but my expertise is probably limited. P.S. I'll uninstall and reinstall the driver again as I did update the driver a week or so ago to the latest driver using geforce experience but didn't uninstall the previous driver (thought nvidia did that for me). Doubt this will fix the problem but worth a shot.