Which part of "start your own thread" did you not understand?

Start your own thread and we will consider it.

All of them.

A lot of the X2's can have the disabled cores unloacked and you get a very cheap quad core :).
Piece of cake to overclock too. My 940Black Edition can go from 3GHz to 3.6GHz with no problem just by...

Best bang for the $ imo atm are the AMD processors. Jump over to the dark side :D

Could be the processor. Was the replacement motherboard identical to the old? If not exactly the same, you will have to do a system repair using the operating system disc.
Might also be the psu that...

If the RAM is different, they will both/all run at the speed of the slowest card.

I would make sure the mobo has the latest bios installed, as that looks to be a reading problem.
What are all the readings under load? Download OCCT and run it for 5 minutes (unless things get too...

That is the temperature of the room/place you are in.

The later processors run cooler because they use less power. My quad runs at 45C full load at 3600MHz.

Do not worry about your idle temps. It is the full load temps that need to be controlled.
What you have now will be no problem.
What is the ambient temps? You will probably see between 20C to 25C...

What are your ambient temps? Make sure the heat sink is firmly attached to the IHS.

He's probably thinking of a Turion :).

There is absolutely NO need to take sandpaper to the heatsink, unless it is not flat. ie; convex or concave.
If one ever needs to, then clean the surface with Isopropyl Alcohol.
That will remove...

Far out mate. A little punctuation would go down well :).
To the OP. First off, no need to be taking off the heat sink just yet.
Take the side cover off the case and have a look at the fins on the...

In regards to the ATI Vs Nvidia card usage, you can use an ATI card on an Nvidia chipset motherboard. The only thing you cannot do is crossfire two or more ATI cards on the Nvidia chipset board.
The...

If it works correctly outside the case, it may possibly be the on/off button/switch that is in the case.
You may have to try putting everything back in to the case and try it again.
Can you get a...

What??

Not much information you are giving away there. What processor are you using? What RAM are you using? DDR? DDR2? DDR3?
Most, if not all, modern motherboards will support more memory than you are...

Thanks for the input, but after 3 and a half years I would say the OP is gone :D

But it's good fun anyway :). I bought my AMD 940 Black Edition quad core and other parts new and went straight into a 20% overclock (after lapping the IHS :)).
The 940 BE runs at 3000Mhz stock and I...

Top of the line at the moment is the i7, so if outright performance is what you want, that's it.
If gaming, then the AMD BE is probably best bang for the buck.

Turn the power off at the wall, then remove the battery from the motherboard. Go and have a cup of tea and a biscuit.
When you have finished, put the battery back in and turn the power back on....

I have different RAM because the 939 system is now my toy. I enjoy overclocking it and having different RAM allows more flexibility.
I have one set of BH-5 RAM which will run 250MHz+ (DDR500) at...

I do not understand it well enough to give a decent explanation, but there is a good read here; http://au.gamespot.com/pages/forums/show_msgs.php?topic_id=25682074
More about how to overclock, but...

The cpu_z is correct. Double Data Rate of 400MHz = 800MHz on the RAM. My cpu_z shows 533MHz for a RAM speed of 1066MHz.

6600's are quad pumped meaning that 266.7 = 1066.8

As Rik said. Different RAM has different timings and clearing the cmos is necessary. May not work in this case, but it is worth a try.
I have several different sets of RAM here that I use on my 939...

Try resetting your bios first by removing the cmos battery on the motherboard. Leave it out for a couple of minutes, then put it back in. Make certain that the power is turned off at the wall first.

Try different software to check on the voltage. Can also get a multi meter and check the voltage at the pins.
A fan pointing at the mobo will help the temps. Make sure the heatsink is on correctly...

Make certain that you have the memory sticks in the correct dimms for them to work in dual channel :). Usually, but not always, the same colour slots are the same channel.
If you do single tasking...

You need to find out why it is running that hot. It will be ok at that temp, provided that that is your loaded temp.
Obviously though, cooler is better :).

Try clearing your bios by removing the cmos battery on the motherboard. Leave it out for 30 seconds, install both sticks of RAM, then replace battery.
You will need to enter the bios to reset the...

The faster RAM will just default to the slowest RAM's speed. Having said that, ideally one should have matching sticks.

A fresh installation of the OS might help, but as you said this has been happening since you got the pc, I doubt it.
I think that if you want better performance, you will need to upgrade your...

Your board is limited to 2Gb which is what you currently have installed, meaning you are at your maximum. Your system however is capable of running 800MHz RAM and you are running 533MHz RAM.
Whilst...

What brand and model motherboard do you have? 945 is the chipset on the board.

Which dual core processor is it exactly? If it is high specced, the problem is probably with insufficient RAM.

Try clearing the cmos for about 15 minutes making certain that the power is turned off.
Reset the cmos jumper and then go into the bios. Set the time and date. Load Optimised Defaults and save and...

No worries. Let us know how you get on.

Not sure exactly where you are here?
Has the one core problem been there all the time? If so, get that warranty you were talking about.