Why can't my DDR3 1600 memory run at rated speed?

[mxnerd]

I bought ASROCK Z68 Extreme4 / Core i5 2400 3.1G this week to pair with 4X4GB Avexir DDR3 1600 (1.65v) I bought a while ago.

It seems the board can only works with the DRAM at 666 Mhz (DDR3 1333), not 800 MHz I hoped for. Even if I turned on XMP 1.2 setting in motherboard BIOS. Whenever I set the speed to 1600 or turn on XMP 1.2, the system won't boot.

my quesion is, is there anyway to make the system run the memory at 1600? I do see the FSB ration is 1:5, so it's probably out of question? And the highest speed the ram can run is probably 680 Mhz at 3.4G at turbo mode?

Do I have to overclock to utilize the full speed of DDR3 1600? That probably is not what I wanted to do.

 

[felang]

Make sure mem voltage is 1.65V

 

[mxnerd]

Make sure mem voltage is 1.65V

It's already 1.65v in BIOS. And ASROCK utility also show it' 1.65v for the memory.

 

[jhansman]

I'd give Asrock tech support an email. They have been quite responsive to my queries.

 

[mxnerd]

Emailed ASROCK twice, the tech just point me to the web page that shows compatible memory, and said if it's not on the page, it's not supported, how convenient is that?

http://www.asrock.com/mb/memory.asp?Model=Z68 Extreme4

 

[john3850]

Most good memory will run at 1600 with 1.5v.
Its cheap oc memory and thats why it needs 1.65.
You should try a different memory companys memory.
My 2 year old mem runs 1600 with 7-7-7 at 1.5 volts.
My sb DDR3 1333 memory runs great at 1.28v through its rated at 1.5v

 

[jhansman]

My RAM (see sig) was not on Asrock's supported list when I bought it, so I just rolled the dice. It booted at 1333, and I was able to change it in BIOS to 1600 where it's been ever since. BTW, mine runs at 1.65v as well.

 

[john3850]

What I am trying to say is the lower the voltage the better the ram.
DDR3 1600 is only one step up from DDR3 1333 so if needs 1.65v it means it did not meet the specs 1.5v so they overvolt it to 1.65 to run normal.
The memory should run good at 1.65v your just outside of intel spec 1.57?
There is much memory at DDR3 2133 using 1.5v-1.60v.

 

[kmmatney]

It also might be the fact that you are running all 4 slots with 4GB of memory sticks. Can you run at 1600 if you remove 2 sticks?

In any case, I don't think you'll notice that much difference. I'd take running the memory at a slower speed if that is what is required for 16GB. That's all lot of RAM!

 

[coffeejunkee]

Answer: you can't overclock your memory using a non-k processor.

(don't be too disappointed, you wouldn't notice the difference anyway)

 

[mxnerd]

Answer: you can't overclock your memory using a non-k processor.

(don't be too disappointed, you wouldn't notice the difference anyway)

Yes, after search the net, found that the performance difference between 1300 & 1600 seems small in real world application.

I'll accept what it is.