question Is an Intel E8400 CPU compatible with an Intel D946GZIS MB?

[apairofpcs]

I have an Intel Core 2 Duo E8400 "Wolfdale" LGA775 configuration CPU.
I have an Intel D946GZIS motherboard with an LGA775 configuration socket.

I did some research on the Intel website regarding compatibility, and here is what I found in the way of Compatibility Charts:
Intel desktop motherboards compatible with the Intel Core 2 Duo E8400 CPU..... http://processormatch.intel.com/CompDB/SearchResult.aspx?ProcNbr=e8400&Lang=en-US
Intel CPUs compatible with the Intel D946GZIS MB..... http://processormatch.intel.com/CompDB/SearchResult.aspx?Boardname=d946gzis

No matter which compatibility chart I use, the MB and CPU are NOT compatible. Am I missing a more recent chart on the Intel website, that includes both the MB AND the CPU? Is it a given that any LGA775 CPU that fits into the LGA775 socket of a MB, is compatible with the MB?

 

[P5-133XL]

Supported processors for D946GZIS

That document was last modified 1/2012.

 

[apairofpcs]

Supported processors for D946GZIS

That document was last modified 1/2012.

I saw that chart, but it doesn't list Core 2 Duo CPUs. If you click on Compatibility Tool in the rectangular box above the chart, you'll get this..... http://processormatch.intel.com/CompDB/SearchResult.aspx?Boardname=d946gzis which is the top link in my post. Note that the highest number CPU is E6700. What happened to the many CPUs with higher numbers? I find it hard to believe that the MB wouldn't be compatible with CPUs with a higher number than E6700.

 

[sdbardwick]

E8400 uses a 1333 MHz FSB. Looks like that board's chipset only supports up to 1066 FSB speeds. So E8400 probably won't work in that board, and even if it does, it will lose 30% of performance.

 

[CougTek]

...and even if it does, it will lose 30% of performance.

30% of the RAM bandwidth doesn't translate into 30% of the overall performance of the system. It might be 3-4% slower all in all.

 

[sdbardwick]

IIRC, Conroe 775 CPU clocks are tied to FSB.

 

[Stereodude]

30% of the RAM bandwidth doesn't translate into 30% of the overall performance of the system. It might be 3-4% slower all in all.

Isn't the multiplier locked though? It may not have the necessary FSB:RAM ratios to support it.

 

[apairofpcs]

E8400 uses a 1333 MHz FSB. Looks like that board's chipset only supports up to 1066 FSB speeds. So E8400 probably won't work in that board, and even if it does, it will lose 30% of performance.

I'm aware that according to the FSB numbers, there is a mismatch. Should I attempt an MB swap at all considering what you've written about the loss of performance, even if you're wrong about the 30% of loss and CougTek is correct about the 3-4% of loss? This level of technical conversation is way over my head, but you guys look like you're having fun throwing around numbers.

 

[Bozo]

The worst that could happen is you would fry the CPU.
In my experience with Intel motherboards, if the CPU is not listed, it won't work.
Intel support for that motherboard ended in 2009. In motherboard years, it is from the stone age.
Intel also says it won't support Win 7.
You could read the specs on the newest BIOS that is available and see if support for bronze age CPUs was added.

 

[apairofpcs]

The worst that could happen is you would fry the CPU.
In my experience with Intel motherboards, if the CPU is not listed, it won't work.
Intel support for that motherboard ended in 2009. In motherboard years, it is from the stone age.
Intel also says it won't support Win 7.
You could read the specs on the newest BIOS that is available and see if support for bronze age CPUs was added.

Your "testimony' was favorable to me, because it doesn't look like I'll be swapping MBs anyway. My desktop is purring along. Considering the MB's age I'll never have any use for it, because I certainly won't be going back in time with the CPU, memory and OS to make it work. It's so sad that I have a new MB that I can't use today or tomorrow. If my MB fails, I'll buy one that allows me some expandability for the future.

 

[Mercutio]

I've had Wolfdale and Yorkfield CPUs on those boards. I've run a Q9400 on one and I have a few E5400s scattered in among much older E6300s. Sometimes a BIOS update is needed, but that's not really an impossible hurdle to clear.