DDR2 800 versus DDR2 1066

AARRGGHHH · Post by **AARRGGHHH** » Thu Jun 07, 2007 3:13 am

I'm pretty new to all this. I'm building a system with an Intel P975XBX2 motherboard and E6600 (Core 2 Duo 2.4 Ghz) CPU. I may eventually upgrade to the Quad Core 2.4 Ghz when the price comes down.

The Intel (and Asus) motherboards are rated as 1066 FSB. However, the same Intel (and Asus) motherboards list the RAM spec as 800. I'm confused. Explanation would be greatly appreciated.

Along that line of thought:

Would it be "overclocking" or "standard procedure" to use the DDR2 1066 RAM?
Will the 1066 give me the better performance that I expect from it at stock settings / no overclocking?
I'm under the impression the 1066 (even though it operates at 2.2 volts) will give me some breathing room if I choose to overclock, is that correct?

Many thanks, for all the guidance everyone has provided over the last couple weeks

Sparky · Post by **Sparky** » Thu Jun 07, 2007 7:29 am

I don't believe the mobo supports PC8500 (DDR2 1066) RAM. See below for link and info from Intel website regarding RAM for 975XBX2.

http://www.intel.com/products/motherboa ... /index.htm

Quote:
Memory: Four 240-pin DDR2 SDRAM Dual Inline Memory Module (DIMM) sockets
Support for DDR2 800, DDR2 667, or DDR2 533 MHz DIMMs
Support for up to 8 GB of system memory
Support for ECC and non-ECC memory

AARRGGHHH · Post by **AARRGGHHH** » Fri Jun 08, 2007 2:50 am

Thank you very much for catching that, I completely missed it. Unfortunately, the Asus also doesn't seem to support 1066 RAM

http://www.asus.com/products.aspx?l1=3& ... odelmenu=2

Dual channel memory architecture
4 x 240-pin DIMM sockets support max. 8GB
DDR2 800/ 667/ 533 ECC and non-ECC memory

I'm curious, why is the DDR2 1066 being manufactured right now? Is it for the SLI boards?

Thanks again

Post by **dicecca112** » Fri Jun 08, 2007 6:35 am

doesn't matter, it'll run fine, and if it has overclocking options it'll run faster than that. You may just manually have to set the default timings

AARRGGHHH · Post by **AARRGGHHH** » Fri Jun 08, 2007 5:24 pm

So if I understood right, you're saying it's okay to run the 1066 RAM? The motherboards I'm looking at both have a 1066 FSB and are rated at 800 for RAM.

Will the system constantly be overclocked if I use the 1066 RAM? I'm not sure I'd want to run it overclocked 24/7.

On the other hand, does the 1066 RAM have more overclocking potential than the 800 RAM?

Thanks again

Post by **dicecca112** » Sat Jun 09, 2007 9:37 am

nope, it'll run at whatever your processer FSB is.

Sparky · Post by **Sparky** » Sat Jun 09, 2007 10:44 am

So if I understand correctly, since the FSB on my E6700 is 1066mhz I could step up to PC8500 (DDR1066) and it would run faster memory speeds than my existing PC6400?

JohntechUPi · Post by **JohntechUPi** » Sun Jun 10, 2007 1:12 am

Well not quite!
With an Intel Chipset you will top out at 800 MHz for memory and if you over clock about 930 - 1030 MHz is about where it will top out.
You have to remember that DDR1066 is running at 533 MHz actual clock frequency and A Intel 1066 FSB CPU is actually running at 266 MHz actual clock frequency.