Core 2 Duo/DDR2 Overclocking question

[kutark]

Hey guys, i had a quick question on Memory regarding a Core 2 Duo system i will be ordering this week. Basically, i want to try for a 3.2 to 3.4ghz OC, my question is should i spring for the DDR2-800 that has the 4-4-4-12 timings, or would i be ok with 5-5-5-15?

 

[CompuTronix]

Hey guys, i had a quick question on Memory regarding a Core 2 Duo system i will be ordering this week. Basically, i want to try for a 3.2 to 3.4ghz OC, my question is should i spring for the DDR2-800 that has the 4-4-4-12 timings, or would i be ok with 5-5-5-15?

This depends on which CPU/multiplier you intend to purchase. DDR2 800Mhz RAM at 4-4-4-12 has OC headroom, 5-5-5-15 can be OC limiting. The following is from wusy's OC guide:

Please use RAM that’s rated:
-DDR2-667 4-4-4-xx (good for ~400Mhz*)
-DDR2-800 5-5-5-xx (good for ~410Mhz*)
-DDR2-800 4-4-4-xx (good for 500Mhz+*) ->Best for E6300/E6400
-DDR2-1066 5-5-5-xx (good for 530Mhz+*)
-Or any other RAM of the above mentioned speed that has even lower timings
*refer to Part2 for maximum Mhz extraction under 1:1 operation

http://forumz.tomshardware.com/hardware/Core2Duo-Overclocking-Guide-v1-ftopict197995.html

The following OC examples help to illustrate how the CPU multiplier variable effects FSB and RAM overclocking.

E6600 @ 3.6Ghz = 400Mhz FSB x 9 CPU multiplier is DDR2 800Mhz RAM at DDR2 800Mhz, 1:1 ratio, 4-4-4-12 @ 1.95 volts.

E6600 @ 3.2Ghz = 356Mhz FSB x 9 CPU multiplier is DDR2 800Mhz RAM OC'd at DDR2 890Mhz, 4:5 ratio, 4-4-4-12 increased to 5-5-5-15 @ 2.15 volts.

E6300 @ 3.2Ghz = 457Mhz FSB x 7 CPU multiplier is DDR2 800Mhz RAM OC'd at DDR2 914Mhz, 1:1 ratio, 4-4-4-12 increased to 5-5-5-15 @ 2.15 volts.

Hope this help. 8)

 

[kutark]

Yes, that helps immensely, i'll probably just pick up the 4-4-4-12 memory to be safe, it is only about ~40 more, so not really that big of a deal.

I'm kind of a "conservative" overclocker, if that makes sense. So i was wanting to shoot for a 3.2 - 3.4 ghz out of it. Really i just wanna make sure the CPU lasts reliably for ~1.5-2 yrs. as thats usually how long i go between major upgrades. So if you guys think a 3.6ghz overclock would be reliable for that long, i wouldnt be horribly opposed to trying for it.

Just for shits n giggles, i'm planning on the Asus 650i board, the e6600 cpu, and probably corsair memory at the lower latency. According to anandtech the asus 650 board is an excellent overclocker. So i'm hoping i'll be ok.

Also, any reccomendations for CPU coolers? I'm pretty much anti watercooling, but im not opposed to massive heatsinks/fans.

 

[NotAPimecone]

Also, any reccomendations for CPU coolers? I'm pretty much anti watercooling, but im not opposed to massive heatsinks/fans.

Tuniq Tower.

 

[CompuTronix]

I'm kind of a "conservative" overclocker, if that makes sense. So i was wanting to shoot for a 3.2 - 3.4 ghz out of it. Really i just wanna make sure the CPU lasts reliably for ~1.5-2 yrs. as thats usually how long i go between major upgrades. So if you guys think a 3.6ghz overclock would be reliable for that long, i wouldnt be horribly opposed to trying for it.

There are no CPU's 100% identical. Every silicon semiconductor device is unique, and as such, has different basic properties of electronics such as resistance, capacitance, inductance, impedance, and transconductance. Although two consecutive serial number CPU's from the same fabrication, with the same stepping codes, may appear identical, they're yielded from different location on the silicon wafer from which they're manufactured, and like diamonds, each has it's own unique flaws.

Even though their dynamic operational characteristics may be very similar, no two CPU's will overclock to exactly the same stable maximum speed, at the same voltage, at the same temperature. Additionally, in a dual core processor, one core will always become unstable before the other. There are no gaurentees that you can reach 3.2 - 3.4Ghz at a reasonable voltage and temperature, even with high end cooling. There's no way to project your OC, or how your CPU will respond until you try.

Hope this helps. 8)

 

[kutark]

Aye, basically pick it all up and hope for the best ;-).

 

[dragonsprayer]

The key is bandwidth u should have 6300-6800mhz 4-4-4-12 and 5-5-5-15 are the same ram they sort the good and bad and test it.

you can push 4-4-4-12 better it will run cooler and cleaner and its worth the extra money - its the sweet spot.

i build gaming systems with all kinds of different brands and speeds - i use ddr2 800 4-4-4-12. play around with the parameters --- voltage, latencies and speed and sandra test - mem bandwidth