A) I would use the Intel Pentium D, model D820.
It's a Dual Core processor with 2MegaByte of L2 cache, and an 800MegaHertz Front Side Bus. (800MHz FSB)
I would also use PC2-6400 ram memory, (DDR2 Sdram at 800MHz)
Using PC2-5300 (DDR2 Sdram at 667MHz) is taxing on the Processor.
If you are using an Intel Pentium D, model D506. It's maximum Front Side Bus is 533MHz. I would NOT use DDR2 Sdram at 667MHz.
Also is taxing on the Processor.
The cache for a Processor is the FIRST memory area, the Processor accesses.
(L1, and L2 for the processors you named. Newer models have an L3 cache also)
It is a small memory area for the processor, and operates at the same frequency rate as the processor does.
(Frequency Rate = 'Speed')
The next memory area the Processor accesses is the Ram Memory.
Ram Memory typically operates at HALF of the FSB of the Processor.
With a D820 you are making the processor's FSB support Step Down, to use the 667MHz ram memory.
With the D506 you are making the processor's FSB support Step Up, to use the 667MHz ram memory. http://www.intel.com/support/motherboards/desktop/d945gtp/sb/CS-026628.htm
More work for the Processor = More Heat
B) Next, how you applied the new Thermal Paste.
Notice I stated N-E-W.
This is because thermal paste can dry up, and also loose it's thermal conductivity properties.
Don't skimp in this area. Thermal paste is C-H-E-A-P!
C) What kind of thermal paste did you use?
The thermal paste that has real silver in it, is an Excellent thermal paste, BUT needs to be applied properly.
Because silver is an excellent conductor of ELECTRICITY, as well as heat.
If too much is applied the excess will ooze off, once the Processor reaches operating temperature.
Means the thermal paste will ooze down off of the Processor, onto any solder joints it can reach, AND the contact pins of the Processor.
This can cause a Short Circuit. May just cause overheating until the wrong solder joints, or processor pins are reached, by the oozing thermal paste.http://www.hardwaresecrets.com/article/274
Proper cleaning of the top of the Processor, and bottom of the Heatsink
The old thermal paste, or thermal pad, needs to be THOROUGHLY removed. Use a plastic scraper
(Old credit card, or one you got in the mail? "Now you too can have a XXXXXX credit card!" Bah, sheesh!)
Scrape off as much as you can. Then use Q-tips dipped in Isopropyl Alcohol. (Rubbing alcohol)
I use 91 percent, (91 percent alcohol, and 9 percent water)
You can use 70 percent, but I do NOT recommend 50 percent.
(50 percent alcohol, and 50 percent WATER)
Isopropyl Alcohol is EXTREMELY FLAMMABLE!!
Use in a WELL ventilated area with NO sparks or flames present!
Takes a LOT of alcohol dipped Q-tips. The top of the Processor, and bottom of the Heatsink, needs to be THOROUGHLY cleaned.
Clean enough you could literally eat off of it. (But DON'T)
D) When you put the Heatsink/Fan combo on the Processor, did you hold the motherboard in the air, and look across the motherboard with a 'birds eye view', at how the Heatsink is sitting on the Processor?
CANNOT be tilted. Has to have the entire Heatsink area, sitting flat on top of the Processor. If you can see ANY, daylight in-between the top of the Processor, and bottom of the Heatsink, START OVER.
E) What kind of Heatsink/Fan combo are you using? May be too small for the job, or not the correct one.
F) Does the computer tower have plenty of room around it? You are supposed to have at least 3 Inches of room, all around the computer case. In your instance I would use more.
G) Taking the side cover of the computer case off, to help cool the Processor. This = NO, unless you have an external fan blo-wing air into the open case.
By taking the cover off you are decreasing the cooling power, of the computer case fans.
The Intel Pentium D, model 820 can use up to 95 Watts of power.
At that maximum wattage usage, the maximum allowed temperature
is 64.1 degrees Celsius.
You are correct. Shouldn't be at 65 degrees Celsius just loafing. (Idle)http://ark.intel.com/products/27512?wapkw=thermal+range+for+pentium+d+processor+820
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