RAM timings/speed

Well, your processor LOVES higher MHz, and timings dont mean anything to it. Timings changing from 7-7-7 to 11-11-11 will be like 1-2% performance difference. This is very different from the past but thats how it is on Sandy and Ivy.

The Sandy Bridge and Ivy Bridge processors have incredibly powerful and accurate pre-fetchers and cache systems, so memory does not play a very big part in gaming performance over all. The higher MHz you have will show up in certain areas as big performance modifiers, but those situations dont come by in gaming very often for these processors. Still, I suggest setting higher MHz rather than tighter timings. Your FPS will maybe get 1fps better by going from 1600MHz to 2133MHz on your processor.
Bulldozer processors on the other hand can show as much as 5-10fps improvement by using high speed memory. The Bulldozer core needs significant tweaking as its pre-fetchers and caching system are terrible. The whole system does not work well with the new module design, and both cores "thrash" each others cache which causes a LOT of trips to system memory for just about everything. So on these processors you will want to have the highest MHz you can get to support the cores. Thankfully, the Bulldozer processor made giant leaps in AMD's memory controller and it is not the best on the market in speed ability. I have seen people OC their RAM to over 3.3GHz on a Bulldozer processor!

 

Those stick are actually really good from what I remember, most RAM now days have very scewed timings with the stuff made for really high MHz having terrible TRCD timings. Your stuff on the other hand is made to run flat timings really well and have low TRCD. I am pretty sure those are Hynix BFR chips... Probably some H9C's. Although depending on how old they are, the chips might be Micron. I bet if you upped the voltage to 1.65v and changed your timings to 10-10-9-27 1T(aka 1N, aka command rate 1) you could hit 1866MHz, probably even 2000MHz. Just remember to raise the VCCIO a bit too. But if they are old Micron, it probably wont work, those chips like some HIGH voltage. Since the kit is 1.5v stock I doubt they are Micron though, that stuff used to sell as 1.7v stock.


If you want to have some real fun overclocking memory, the Samsung 30nm sticks sold as 1600MHz speed are easily capable of 2300MHz+ on Ivy Brudge, I have seen some up at 2600MHz even. And 8GB of that stuff is like $40

 

No you shouldnt buy the Samsung's and use both at the same time, they are most definitely very different chips and will respond quite different to voltages, timings, and driving forces.


Your stick will handle up to 1.65v perfectly fine, you just have to worry about your memory controller. The default voltage on that is something like 1.1v, and the controller voltage is never supposed to be more than .4v apart from the RAM voltage. So if you raise the vDDR to 1.65 then the VCCIO needs to be raised to 1.25v. Just raise both at the same time by the same amount and you will be fine.

 

FYI, Most voltage I have seen pushed to the RAM on Ivy Bridge with air cooling is 1.75 volts. I dont recommend that for 24/7 though, just short benchmark runs or to test what something is capable of. Technically you are not supposed to go above 1.5v on the RAM, that is because of the stock VCCIO voltage. The Intel whitepaper for Sandy Bridge says that absolute max is 1.6v on RAM, although I know LOTS of people who run 1.65v for 24/7 use perfectly fine.

Core voltages I have seen people use as much as 2.1v when running LHe or LN2. Max I have seen anyone run 24/7 on air is 1.375v, and max benchmark only on air I have seen is 1.45v. Doesnt mean any of those voltages are safe though, I wouldnr run more than 1.35v for 24/7 use as any higher will make your temps be way too much on Ivy Bridge.