On the evidence that we have, although no really reliable tests have been made on the PSU, we can as you have replaced it discount the PSU.
The same applies basically to the graphics card, as you have replaced that as well.
Memtest passed you reported on both sticks testing ONE stick at a time on all 8 checks of the ONE cycle, and GOOD as Memtest is, it DOES not categorically mean that the ram is perfect.
We have as far as possible eliminated any question regarding the graphics drivers insofar as we have tried an older certified driver and now the most recent offered BETA driver.
NOW we have errors that we did not have before, not only when you are loading that game League of Firends but simply whilst browsing AND more concerning one of those errors is now related to the USB Hub.
Modern PSUs can ONLY be tested using specialist equipment, the old idea of testing with a multimeter, is a non starter.
I would recommend the following BUT ONLY ONE step at a time and testing after each step.
1. Run this please
BE AWARE PLEASE that when the program runs there is a small flashing graphics on the top right of the program window.
The reason I am suggesting this is that according to Pitstop you have 5Gb of temporary files.
It will not solve the problem, but it is certainly of benefit to clean up a little.
2. Run this please using ALL available troubleshooters
IF STILL NO SUCCESS Please proceed to the steps below
1. YOU check that all connections to the motherboard including the main 24 pin from the PSU and the 4/6 pin are properly seated and the clip of the connector is in place. That the SATA power connector to the HDD, the DVD (if that is SATA as well) and to any other hardware are also properly in place. You should of course include in your checks all the connections to the various headers - the USB, front panel Power and audio etc. Please also check the SATA data cables.
I am sure you do not need me to remind you but where these connections are on the edges of the board always of course support the edge of the board when disconnecting and re connecting.
Generally it is NOT a good idea to disconnect and reconnect as of course it simply serves to weaken the securing slots into which the ram and the graphics card and many others insert, but in your case, I think it is vital that ALL connections are checked.
2. If you have SPARE SATA data cables I would replace the one to the HDD especially as it WOULD not be unknown for that to be the problem.
3. IF you do not find anything immediately obvious and the problem continues I would then test with just ONE stick of ram. I cannot remember NOW if you have actaully done that.
I am not refering to MEMTEST but to RUNNING the system.
IF that still produces the errors i would test WITH the other ONE stick.
If that still produces errors I would return to both sticks.
4. I would then enter setup and load DEFAULT settings.
You may wish to take the precaution here of SAVING the current BIOS setup to the HDD - see your motherboard manual as to how.
TEST with default settings
IF we have hit the jackpot and I think it is a rather LARGE IF, then of course at least we have identified the posible cause.
5. IF THAT still fails, when you mentioned earlier that you have at one time replaced the thermal compound/paste on the CPU please see THIS
That is a guide written by Digerati a GeekstoGo Staff Member and one of our experts on PSU isuues and thermal matters.
At this stage, I believe it worthwhile that you consider this, not necessarily JUMPING in to replace it, but to ascertain if your previous method met with these guidelines
The common mistake is TOO much paste.
If you have doubts I would attend to the issue and test again.
6. I would if you have reached this stage with no result consider the suggestion in my post 27
This if it configures correctly will go someway towards proving if this is all caused by driver or programs non compatability to windows 7.
7. If it is still NO success please post and I will re consider the position.