Bro. Your PSU has 2 rails and a total of 20A. Thats a theoretical maximum before shutdown of 240W on the 12V rail. Thats MAX>
But, as you have a poorer quality unit, it not only has an old ATX design standard, it also misses out on undervoltage protections (protects against brown-outs).
The ATX design standard means that the 12V+2 rail is dedicated (via your mobo cpu power cable) to the CPU. Thats a full 1 rail, 10A of the total 2 at 20A used and not available to the motherboard, graphics card, ram etc.
So in actual fact, you're looking (with de-rating) at about 8A or ~100W on the 12V+1 rail before shut down (which is what is happening).
Now, you have a E6600 with a TDP of 65W.
A 550Ti - 116W
And some other gear 50W (hard drives etc)
That's ~230W. Correct, but your PSU can only provide 100W on the 12V rail that the 550Ti is on, and it needs more. The PSU is too weak.
No you are wrong. He have 460 watt which it can support GTX 550 Ti and CPU. Plus i don't think his PSU is dual raid unless op provide a specs or model number for us can research it.
Bigfella what i should do?
To determine what is wrong,
With the Celeron CPU installed;
- Test each RAM module individually using Memtest, or Windows' Tester
- Remove dust and grime
I hvae tested the memory using memtest. No problem identified. I think the mobo is not fully compatible to this CPU.
NO Intel have replaced a new cpu.
Then why are you got blue screen with this CPU?
That is the CPU problem, not your motherboard nor RAM.
BTW have you use PSU tester?
You have no idea. The PSU has a total of 32A on the 12V rail across 2 rails. 1 is dedicated to the 12V rail for the CPU, that is 22A gone. The other is 20A but can only deliver 10A of those (due to the design).
Derate it and you get what I was saying before.
You are assuming that the processor is the problem without going through thorough troubleshooting steps. It could be the RAM, motherboard, power supply, a hard drive or software giving him problems. The last thing I would suspect is the processor at this point but I would not rule that out either.