Is my RAM too fast

[markmcrobie]

I have a Core 2 Duo E6600 @ 2.4Ghz, 1066Mhz FSB.

My RAM is 2GB Samsung DDR2 SDRAM @ 667Mhz. I read somewhere (maybe Wikipedia) that in *some* setups, with a 1066Mhz it's actually better to have RAM @ 533Mhz, as 533Mhz is nicely divisible by 1066Mhz, i.e. the FSB.

Is this true?

Thanks

 

[Mondoman]

In certain cases. Check out this article:
http://www.madshrimps.be/?action=getarticle&number=1&artpage=1962&articID=472

 

[markmcrobie]

Reading that article, I deduce that there are *no* situations where 667Mhz RAM is better than 533Mhz, when using a Core 2 Duo and 1066 FSB?

If that's the case, is there any way I can (safely) either decrease my RAM to 533 or increase my FSB to 1334 (i.e. 667 x 2)?

Thanks

 

[Bobsama]

I'd say reap the benefits of a small overclock. Up your FSB to 1333mhz and enjoy your processor and RAM at full-speed.

If you are using a 1:1 setup, then the memory you currently have is underclocked to 533mhz. Boost it and you'll be having a good old time.

 

[markmcrobie]

How do I up the FSB to 1333?

 

[Bobsama]

Your computer's setup (if memory serves) is a 266mhz FSB with 9x multiplier. Up the FSB to 333 and you should get a 1333mhz FSB (because, as we all know, 333*4=1333, processor will be at 333*9=2997 or about 3ghz).

I'd say the vast majority of motherboards will be able to do that FSB. It'll be standard for a E6600 (soon to be replaced by E6650?) to run on a 1333mhz FSB. No harm done... and I doubt you'll run that processor for the 8-12 years it will take for it to die.

 

[markmcrobie]

How do I change that setting?

I have a Dell DXP061 motherboard, and the clock generator is an IDT CV174 CPAG.

Clockgen and Systool both don't recognise my motherboard/clock generator.

 

[Crashman]

You should try reading Tom's Hardware Guide. It's been repeated many times that FSB1066 runs at 266MHz (Quad Data Rate), and DDR2-533 runs 266MHz (Double Data Rate), so that the two are the same speed. It's also been repeated many times that Dual Channel mode makes up the bandwidth difference between Quad Data Rate and Double Data Rate.

Having said that, DDR2-667 might still be faster at its rated speed simply because clock cycles are shorter at 333MHz than at 266MHz. This is about CAS latency, which is measured in clock cycles.

Of course, most of us could simply go into the system's BIOS and choose "533" plus drop all the latency values by one cycle. Others might see this as an opportunity to overclock the CPU FSB to 333MHz after putting the RAM to 533, which would cause it to be "pushed up" to 667 as you overclock the FSB. But d00d, you got Delled.

See what you can do in BIOS. Heck, there might even be a secret jumper on the motherboard somewhere that unlocks overclocking perameters. So do your investigation.

 

[markmcrobie]

I can do absolutely nothing in the BIOS - I've never seen a BIOS with so few user-changeable options in my life. Then again I've never owned a Dell in my life.

I can't even turn off onboard sound.

 

[Bobsama]

Ouch. Try to ID who made the actual board. If you can do that, see if you can find a compadible BIOS so you can flash it. I doubt there is much out there...

The RAM is right now likely underclocked, making the extra investment useless (you upgraded, right?).

As was previously stated... "But d00d, you got Delled". A rule of thumb... never buy Dell. Build your own if you can; it will turn out much better.

If I was in your shoes, I'd sell the motherboard on eBay or something and buy another board from some cheap manufacturer that has some overclocking potential. It'll probably void your warentee, but since when did Dell act upon their warentee? Even if I got that dell for free, I'd sell it to buy something good. I realize that's probably not an option for you.

 

[markmcrobie]

Actually I stupidly picked the 667Mhz RAM when I was "building" my PC on the Dell web site - it cost an extra £94 over 533Mhz RAM, but I just thought faster = better.

 

[Crashman]

Not stupid, if you upgrade to a 1333MHz FSB processor you'll need at least DDR2-667.

 

[markmcrobie]

Which processors have a FSB of 1333?

Since I bought a Core 2 Duo E6600 I don't intend upgrading it any time soon!

 

[Crashman]

Intel's next generation Core 2's will have 1333FSB for the high end.

 

[Mondoman]

Reading that article, I deduce that there are *no* situations where 667Mhz RAM is better than 533Mhz, when using a Core 2 Duo and 1066 FSB?

Your deduction is wrong -- perhaps you misread the article? It all depends on the specific app and the latency settings. For example, (from the article):
Quake 4 800x600 results, from better to worse:
DDR2-667 CL3
DDR2-667 CL4
DDR2-533 CL3
DDR2-667 CL5
DDR2-533 CL4
DDR2-533 CL5

However, it's obviously better to overclock the FSB to be in sync w/DDR2-667.

 

[Bobsama]

Not only does the memory preform better, but your processor will be so much faster. Kinda makes you happy that Intel didn't drop NetBurst architecture earlier; the experience with high clockspeeds ends up making the best overclocking CPU's available... huge gains on speed with good stability. The current C2D setups are at about half their potential.

Anyways you could buy a new E6650 at release and sell your current on eBay for about ~$250. Your FSB will be factory-speed 1333mhz FSB; you will get the full speed out of your RAM.