Sandybridge mobo + 1.65v O/C ram

[donzgod]

Hi guys,

saw a few articles round this discussion going back to last year but nothing really recent. Is running my corsair 1866 ram at 1.65v harmful, long or short term to my i5 2500 CPU? My motherboard is - asus p8z68-v/gen3 - and ram - Corsair CMT8GX3M2A1866C9 2x4GB DDR3-1866 CL9 Dominator GT

Any current feedback, articles etc would be awesome, thanks!

 

[arthurh]

Hi guys,

saw a few articles round this discussion going back to last year but nothing really recent. Is running my corsair 1866 ram at 1.65v harmful, long or short term to my i5 2500 CPU? My motherboard is - asus p8z68-v/gen3 - and ram - Corsair CMT8GX3M2A1866C9 2x4GB DDR3-1866 CL9 Dominator GT

Any current feedback, articles etc would be awesome, thanks!

I really do not have any links for you but here is my take on it.

When SB first came out all there was available was 1.65V ram and the CPU was rated for it. I bought some myself.

However when the 1.5V ram came on the market I decided to run that instead. My reasoning, right or wrong, is since the memory controller is on die the lower voltage would generate less heat internally in the CPU it self. Since I OC this seemed like a good thing to me.

So if your not going to OC, or even if you are, the CPU is rated to work with that rated volage. I just equate lower volages mean less heat meaning perhaps a longer life for my CPU even OC'd @ 4.5GHz 24/7.

Just my two cents on the subject.

 

[jsc]

I would run your RAM at 1.5 volts and DDR3-1600 speeds and try to tighten the timing a little.

Not too well known, but here is what Intel has done:
http://www.tomshardware.com/news/Intel-Overclocking-Protection-Plan-Processors,14519.html

The plan says it only applies to the "K" models,but except for the unlocked multiplier, the internals of the chips are the same. At the very least, it implies that 1.65 volts is not good for the IMC. Besides, you will notice little, if any, difference between the two speeds.

Here's a thread we have:
http://www.tomshardware.com/forum/forum2.php?config=tomshardwareus.inc&cat=29&post=272599&page=1&p=1&sondage=0&owntopic=1&trash=&trash_post=&print=0&numreponse=0&quote_only=0&new=0&nojs=0

 

[blazorthon]

Sandy Bridge CPUs are designed for 1.5v RAM. Using 1.65v RAM can shorten the long term lifespan of the Sandy Bridge CPUs, but it should not cause short term problems.

EDIT: By personal estimation, the CPU should still last around two to three years or so. However, this widely varies. Some lucky people will get an above-average CPU for it's model that lasts as long as the average CPUs of the same model would with 1.5v RAM. Some people get bad CPUs that can barely last as long as the average ones would even at 1.5v. However, I think that two to three years is a good estimation for the lifetime that you should expect.

1.65v RAM is usually only used on a SB CPU for extreme memory overclocks. Due to a Sandy Bridge CPU not being bottlenecked by memory bandwidth or latency like the previous Intel and the AMD CPUs, this only helps for certain applications and not many of them. For example, rendering and archiving are two great examples of the few types of programs that are significantly improved. Some folding programs also like high performance memory. Gaming does not see much benefit at all, although I did once read that the minimum frame rates do improve a little from faster memory.

AMD CPUs and older Intel CPUs are often more bottlenecked by RAM performance, although even then, it's only to a point. For example, the FX CPUs need about 25% higher memory frequency to have the same memory bandwidth as Sandy Bridge because they have an inefficient controller that doesn't make the best of it's RAM frequency. It also needs to have latency timings several notches below a Sandy Bridge CPU to get similar latency.

 

[RetiredChief]

There are two threads on this topic. Condensed version:
1) Intel's spec for Ram voltage - 1.50 +/- 5% (max E = 1.575)
2) A little less clear, and my depend on who you get when doing a RMA is the freq. Appearently Intel is stating the max freq is 1333.
3) Intel is offering a OC warrentee. $25 for the i5-2500K. Basically this is a NO ask, one time exchange, if you damage the CPU thru OC. even if you exceed the 1.5V max Vcore voltage.
Added - Here is a link: http://www.tomshardware.com/forum/forum2.php?config=tomshardwareus.inc&cat=31&post=333313&page=1&p=1&sondage=0&owntopic=3&trash=0&trash_post=0&print=0&numreponse=0&quote_only=0&new=0&nojs=0
End added
Max Ram voltage can be linked to the mak Vcore sence the controller is on die. The rational for the max Freq (1333 is the spec) may be linked to the increased current in the memory controller. As Freq goes up empeadance decreases and current increases.

Anyway, I reused my DDR3 1600 CL7 @ 1.60 V. Have Not bought the "extended" warrentee yet.

 

[donzgod]

Awesome, thanks heaps for the comments and links guys! !!