DDR3 2400 1.65V, any reason not to use this?

[bgc99]

I'm going to build a system with an I7-4770K and most likely an Asus Z87-Pro mobo.

Is there any down side to using DDR3 2400 1.65V ram vs something slower running at the standard 1.5V ?

All 2400 on Newegg is 1.65V . Does 1.65V cause any longevity or stability problems?

Thanks,
BGC

 

[Essence_of_War]

Is there any down side to using DDR3 2400 1.65V ram vs something slower running at the standard 1.5V ?

1.65V is out of spec for Haswell (and I believe, all previous intel sockets using DDR3). It certainly could cause longevity and stability problems. It probably won't, but unless you're gaming on the igpu and trying to eek out every last drop of perf, there are pretty sharply diminishing returns from faster RAM.

 

[bgc99]

From the Haswell memory scaling artical here at AT:

For discrete GPU users, recommending any kit over another is a tough call. In light of daily workloads, a good DDR3-1866 C9 MHz kit will hit the curve on the right spot to remain cost effective. Users with a few extra dollars in their back pocket might look towards 2133 C9/2400 C10, which moves a little up the curve and has the potential should a game come out that is heavily memory dependent.

I wouldn't pay a premium for it, but a current deal makes it a little cheaper or at least on par with ram that is a bit slower. The article mentioned the 2400 so I was just wondering if the 1.65V would make it less desirable, but I guess if it did they wouldn't mention it.

 

[Blain]

The JEDEC DDR3 standard is 1.5v.

 

[Deders]

I think the spec is 0.5v away from the VTT voltage, which I believe (pleases correct me) is right on the edge for processors since Sandy bridge. Too close for some but if you overclock and raise your VTT then you should be within spec.

 

[bgc99]

Yep, will probably stick with 1.5V just to be safe.

Thanks

 

[kcsupratt]

bgc99, PM me. I have some stuff you are looking for in your new build. All new and great price

 

[Morbus]

I got 1866 @ 1.5V because that was the fastest I could get for that voltage.

 

[UaVaj]

I got 1866 @ 1.5V because that was the fastest I could get for that voltage.

that would suggest that 1866 @ 1.5v is the "current" grade A standard for ddr3.

currently running 1600 @ 1.35v. this would suggest these are underclock and undervolted 1866 ram.

on the other hand. 2400 @ 1.65v. this woud suggest these are overclocked and overvolted 1866 ram.

at the end of the day. if the chip itself can handle the speed, timing, and voltage. you can always flash the SPD to your custom profile.

of course your mileage will vary.

 

[Adamantine]

I have some so called "2400" rated at 1.65v running 2200 at 1.5v. They have Hynix MFR IC's under the heatspreaders.

The specs are kinda worthless since they're out of spec anyway. They're pretty much only good for RMA'ing if they don't work at the advertised speed.

I test all ram that I buy regardless of what the advertised ratings are since they're probably lying if they're not following official JEDEC specs. I've gotten some of the JEDEC value ram that wouldn't run at 1.5v (had to use 1.6v) even though it was listed as a 1.5v part, although this was back in 2008 and I didn't get replacement ram until I got the 2400 mentioned above.

 

[bryanl]

The fastest DDR3 chips are 2133, but I've never seen anything faster than 1600 used on any stick, and no DDR3 chips are over 1.50V.

 

[DigDog]

"ddr3 ram running at 1.65v doesn't exist"
http://www.anandtech.com/show/7575/corsair-vengeance-pro-review-2x8-gb-at-ddr32400-101212-165-v

 

[omeds]

I've had a 2666mhz 1.65v kit with my 4770k since release, seems fine so far (around 12 months now).

 

[zir_blazer]

1.65V isn't JEDEC standard but nearly all of the high end Memory Modules I can think about uses that Voltage.
What the Memory Modules manufacturers do, is purchase DRAM chips, bin them, and assemble them with the PCBs into modules. You can say that a 2400 MHz 1.65V module is just a factory overclock. Because there should be more binning and testing involved into those more expensive parts, I would say that they should be more reliable than value parts. If anything, these should have no problems running 1.5V at a more conservative Frequency (1600-1866 MHz) in case you don't like 1.65V.

 

[Morbus]

Please, guys, there's 3200MHz DDR3 RAM.

Yeah, that's TWICE the speed that haswell is specced to run. Granted, I don't think you can get it off your normal PC parts shop, but those will sell you 3000MHz DDR3 without a problem.

 

[UaVaj]

there comes a point when it is better to just put DDR3 3200 stickers on the outside of the case vs actually installing DDR3 3200.

http://www.anandtech.com/show/7364/memory-scaling-on-haswell/8

 

[Blain]

1.65V isn't JEDEC standard but nearly all of the high end Memory Modules I can think about uses that Voltage.

They aren't "high end", they are just overvolting those modules to allow them to run stable at a higher clock speed...
That is not "high end".
High end memory would look like this...

High clock speed... Low latency... Low voltage...
My views are as follows.

If I were shopping for high quality memory, I would use the following parameters as a guide...

* DDR3 rated at 1.5v or lower
* DDR3 rated at the lowest CAS I could afford
* DDR3 rated at the highest clock speed I could afford
* Limit the scope of my purchase to G.Skill, Mushkin, Samsung, Corsair XMS or Crucial (non-Ballistix)

While not wavering on the voltage point, I would balance the other issues with my budget.

Remember, my goal is not pure "benchmarking" performance, but simply finding the highest quality memory I can afford. ^_^

The only reason I pay a premium for low latency, high speed, low voltage memory is...
Quality and quality alone.

1.5v is the JEDEC DDR3 voltage standard.
Stay with 1.5v or less if you can afford it..

 

[bryanl]

no DDR3 chips are over 1.50V.

"ddr3 ram running at 1.65v doesn't exist"
http://www.anandtech.com/show/7575/corsair-vengeance-pro-review-2x8-gb-at-ddr32400-101212-165-v

I searched but could not find that quote elsewhere, and your link shows no chips, 1.65v or otherwise, but Corsair Vengeance has been produced with Samsung K4B4G0846B HYK0 chips:

The K4B4G0846B HYK0, which is not a 2400MHz device, has timings rated at 1.35v and 1.50v, not 1.65v, and it tolerates up to 1.975V:

http://www.samsung.com/global/busin...oduct/2011/8/29/923862ds_k4b4gxx46b_rev12.pdf

 

[Deders]

When DDR3 came out for lynnfield and Nehalem it was rated at 1.65v, it was only later that 1.5 became standard.

From what I remember DDR3 n AMD chipsets had to run even higher, around 1.8v

 

[Blain]

DDR2 was 1.8v

 

[mikenz]

http://www.gskill.com/ claim to have the worlds fastest RAM @ 4404 Mhz

 

[dorion]

When DDR3 came out for lynnfield and Nehalem it was rated at 1.65v, it was only later that 1.5 became standard.

From what I remember DDR3 n AMD chipsets had to run even higher, around 1.8v

Man it was the Intel LGA775 chipsets that were pushing the voltage limit on DDR3. AMD users had already been dealing with over-specced high voltage ram for Intel chipsets for almost two years before Nahalem came out with a recommended max voltage to prevent the new IMC voltage from damaging the rest of the chip.