underclocking & undervolting DDR3

cokecan

cokecan

cokecan

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Hi guys

It's been a fair few years since I've done any overclocking or similar (I'm talking socket A kinda stuff!) so after a bit of advice really.

I'm looking at building a very low power/low heat system, I have my eyes on a decent low power ITX board that has support for up to 8gb DDR3 1066mhz ram. Now I already have 8gb DDR3 1600mhz so could I underclock and undervolt it to run at 1066mhz instead?

Thanks in advance :)
 
Hi there,

May I ask what specific DDR3 kit you have? I reckon you should be fine as most DDR3 modules default at (and are designed to run at) 1.5V 1066MHz until you tell them otherwise.
 
If it's any help. I have some Kingston HyberX Blu it should run at [email protected] however I run [email protected], totally stable.

Much depends on components I have my entire system under volted including CPU and motherboard chipset. I use to use a OCZ 600w, however I switched to a Seasonic X650 and found I could undervolt more due to increased stability of the Seasonic over the OCZ PSU.
 
will the mobo automatically set any of these to the max speed the cpu and chipset support or will it be better if I set it myself in the bios?
 
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When I lowered voltages it was trial and error i'm afraid. I reduced voltages until something crashed (on CPU load / burn) then increased voltages.

Takes some time to work out what voltages you can run, however worth it if your keeping PC a while. I took CPU temps down maybe 15c, and couple of degrees of chipset voltages. I also have the theory that lowering voltages increases reliability, certainly voltage regulators under less load.
 
Also run fewer physical DIMMS to save a little bit more power and heat - ie: just have 2gb or 4gb (you said you had 8gb).

Then under-clock it.
 
ok thanks guys. I have 2x4gb sticks. looking at bundling a i3 2120T with the intel board and this ram to use as a media PC and file server but to also run a few VM's on so looking to have plenty of ram for that. Hopefully I'll have a decent idle power consumption and a load power consumption that's still damn low.
 
After reading this I tried undervolting my ram, I got this to 1.39v at 1600Mhz 9-9-9-24-1t. 10 Passes of Intel burn test with max ram and 12 hours Prime95 blend sable, less heat and power is always good! now time to try my VTT.
 
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matty114 said:
After reading this I tried undervolting my ram, I got this to 1.39v at 1600Mhz 9-9-9-24-1t. 10 Passes of Intel burn test with max ram and 12 hours Prime95 blend sable, less heat and power is always good! now time to try my VTT.
Click to expand...

You've probably used more electricity running 12 hours of Prime95 than you'll save in months, maybe even years of use with slightly lowered DRAM voltage.
 
Surveyor said:
You've probably used more electricity running 12 hours of Prime95 than you'll save in months, maybe even years of use with slightly lowered DRAM voltage.
Click to expand...

Well true but I'm not really bothered about the power usage i just want lower temps. I didn't test just my ram i got my PLL at 1.586 down from 1.83, Vcore from 1.370 to 1.360 and turned my PCH down(Can't remember what it was). Testing my VTT at 0.921 now and seems to be ok so far after 6 hours of prime. I have only had the cpu and mobo for a week so i am still testing my overclock and getting it perfect, will be doing a final 24 hour prime blend tomorrow to check if its all sable.
 
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