Important question... (to me, obviously!)

[Celador]

Am still with the trusty XP3200 rig, dreaming (as a family man these days) of justifying the cost of upgrading to a Core Duo E6600 based system. Have started meself a little "PC fund" and have an end in sight.. However, one thing I need to know concerns cpu & memory speeds.

As far as 32-bit PCs are concerned, I know that the done thing is to run cpu and memory clocks synchronously. However, looking at a Conroe motherboard and memory combination, I am confused by the fact that the Core Duo chips run at 1066 while the memory is at DDR800. There are some uber-pricey 1066 memory and boards out there but this non-synchronous situation doesn't seem to be an issue.. at least the majority of board giving it "Core Duo ready" only support 800/667/533 memory speeds??

Someone wiser please explain it to me

thanks in advance,
Cel

 

[jake000]

A core2duo cpu is quad pumped on the FSB (front side bus). So the 1066 is just the ram at 266*4. All you need for default speeds on a core2duo cpu at 1066 is PC4200 DDR2 ram. Faster ram, such as PC2 6400 (800) would be overkill. The reason so many people buy PC2 6400 (800) ram is because the core2duo cpu's overclock very high.

With PC2 6400 (800) ram, its default speed would be 400. Quad pumped, that would be 1600 (instead of the 1066) and therefore your cpu would be overclocked.

It may also help you to imagine old ram, such as sdram that ran at 100mhz and 133mhz. When DDR came about at PC2100 speeds, it ran at 266mhz which was a (D)ouble (D)ata (R)ate of 133mhz sdram.
With DDR2 ram, its just a double od DDR and thats how the speed comes about. So, PC3200 DDR ram is 200FSB doubled because its double data rate, which is 400 and then the new DDR2 PC6400 ram, is 400FSB doubled to 800.

I hope this helps you and sorry if it confuses you, its hard to explain when typing compared to telling someone face to face

 

[mcc49]

Yea basically at stock speed C2D only needs PC4200 RAM but since the price different between PC4200 RAM and PC6400 RAM is minimal, people tend to spend a little bit extra on the faster RAM to get the most out of the C2D potential.

 

[furnace]

Plus you get a lot more space to overclock with 800Mhz RAM

 

[Celador]

I hope this helps you and sorry if it confuses you, its hard to explain when typing compared to telling someone face to face

Appreciate you taking the time Jake (and the other guys); as you say, hard to get the message across when not f-t-f.

So does this then mean that the C2D E6600 will need to ramp up to 1600 (ok, I mean from 266 to 400) to be in sync with the DDR800 memory? That's 150% on the reactor Jim...! And they do this???

 

[mcc49]

yes the C2D will be doing 1600mhz FSB if you pump it up to 800mhz DDR, a lot of people can achieve this with decent cooling but not all CPU are the same so if yours cant reach this speed just simply put a divider in which allows you to run the RAM at 800mhz while keeping the FSB lower.

 

[Celador]

yes the C2D will be doing 1600mhz FSB if you pump it up to 800mhz DDR, a lot of people can achieve this with decent cooling but not all CPU are the same so if yours cant reach this speed just simply put a divider in which allows you to run the RAM at 800mhz while keeping the FSB lower.

Like your style chap! Not really pushed my rig re overclocking to be honest - have always been bit shy of pushing too hard and making bad things happen! Don't ger me wrong, changing the divider on a 2500 barton to make it a 3200 I can handle but some of the obvious "refinements" of the process of overclocking is well scary without someone who knows things next to you!

 

[BillytheImpaler]

Don't worry, Celador. Overclocking has become a lot more urbane than it used to be. You used to have to futz around with jumpers on the mobo, pin mods, volt mods, pencil mods, etc. All of these are ancient history. Now everything is done in the BIOS. All new CPUs also have emergency throttling capabilities as well so overheating one and burning it up is no longer much of a concern.

Dive in headfirst and enjoy it.

 

[Celador]

Don't worry, Celador. Overclocking has become a lot more urbane than it used to be. Now everything is done in the BIOS.

I hear you man; am not averse to getting to grips with BIOS as it goes but tell me... exactly how much a) hassle and b) improvement will I notice (real world use) by looking to try and clock my brand new E6600 up to 150%???

After all, along with the E6600 I am planning to put in 4Gb of RAM and as I am coming from a decent if ageing 32-bit system, I am gonna notice a BIG improvement in general performance I'm guessing (I'd better for the $$ lemme tell you!) just from running the CPU at stock with 533Mhz memory..

Whaddya think??

Am doing a lot of photo/video stuff at the mo (new Dad, ahhhhh) and not really playing that many games right now. Am planning on a fairly ordinary GPU for now (512MB EVGA 7950GT, KO Superclocked, PCI-E (x16) , Mem 1450MHz, GPU 600MHz, 2 x Dual Link DVI @ £127 +vat). That said, like I mentioned earlier, my lot soon cottoned on to the easy tweak of the Barton XP2500+ to XP3200+ with a simple tweak of the multiplier and if the o/c jump for the E6600 up to 1600Mhz to be in sync with DDR800 memory is similarly achievable, I need to buy the right memory for sure!

Any advice humbly received

Cel