RAM timing, voltage, CAS latency

I am looking at upgrading to 8gb DDR3 1600. I found three that I think would do the job but would like some input regarding these choices. I'm kind of stuck.

Would the 1.35V Mushkin sticks save any energy over the 1.5V sticks? Or would performance suffer because of it? Would i even notice the difference? Going by timing and latency alone it seems the Corsair is the clear winner (speed wise).


thanks


1. G.SKILL $44.99
Learn more about the G.SKILL F3-12800CL9D-8GBSQ

Model
Brand
G.SKILL
Model
F3-12800CL9D-8GBSQ
Type
204-Pin DDR3 SO-DIMM
Tech Spec
Capacity
8GB (2 x 4GB)
Speed
DDR3 1600 (PC3 12800)
Cas Latency
9
Timing
9-9-9-28
Voltage
1.5V
ECC
No
Buffered/Registered
Unbuffered
Multi-channel Kit
Dual Channel Kit
Heat Spreader
No

2. CORSAIR $48.99
Learn more about the Corsair CMSX8GX3M2A1600C9

Model
Brand
CORSAIR
Series
Vengeance
Model
CMSX8GX3M2A1600C9
Type
204-Pin DDR3 SO-DIMM
Tech Spec
Capacity
8GB (2 x 4GB)
Speed
DDR3 1600 (PC3 12800)
Cas Latency
9
Timing
9-9-9-24
Voltage
1.5V
Multi-channel Kit
Dual Channel Kit
Features
8GB (2x4GB) DDR3 SODIMM kit for 2nd Generation Intel Core i5 and i7 notebooks.

1600MHz

9-9-9-24 latency

1.5V

Auto-overclocking (no bios configuration required)

3. MUSHKIN $42.99
Learn more about the Mushkin Enhanced 997037

Model
Brand
Mushkin Enhanced
Series
Essentials
Model
997037
Type
204-Pin DDR3 SO-DIMM
Tech Spec
Capacity
8GB (2 x 4GB)
Speed
DDR3 1600 (PC3 12800)
Cas Latency
11
Timing
11-11-11-28
Voltage
1.35V
ECC
No
Buffered/Registered
Unbuffered
Multi-channel Kit
Dual Channel Kit

 

I think you are limited to 1333 per ARK

Intel® Core? i7-2620M Processor (4M Cache, 2.70 GHz))

 

That's what I thought until i saw this:

Newegg.com - G.SKILL 8GB (2 x 4GB) 204-Pin DDR3 SO-DIMM DDR3 1600 (PC3 12800) Laptop Memory Model F3-12800CL9D-8GBSQ

"Keith
12/16/2011 3:21:42 PM
Tech Level:
Ownership:
Verified Owner
Works Great - Lenovo T420 Sandy Bridge
Pros: Works out of the box. Runs at DDR 1600 on the Lenovo T420 i7. Yes, it does run at DDR 1600 on the i7-2640M, despite what the intel webpage says about that processor.

Core i7-2640M Sandy Bridge. CPU-Z reports all JEDEC Values as advertised. 800MHz 9-9-9-27-39.

There's a JDEC for 977MHz at 11-11-11-33-48 for anyone that adventurous.

Type: DDR3 - Channels # Dual - Size 8192 MBytes - DRAM Frequency 797.6MHz - etc, etc, etc.

Cons: Didn't come with nano-bots to install itself for me.

Other Thoughts: Confirmed speed with MaxxMEM2"


But in my case, I'm going to be using an i7-2820QM.

 

If you want 1866mhz you can get Hynix PnP ram or corsair XMP ram.

Or you would have to buy thaiphoon burner to flash a PnP or XMP profile onto the new ram you buy, it's not too hard to do.

I have my Samsung 1333mhz ram at 1600mhz with the help of the XMP enhancement feature of thaiphoon burner.

Why not go for 1866mhz if you're upgrading anyway?

 

I guess i just didn't know that. If u think I can get even more performance from something like this than that may be the route i take. The next step would be to learn how to do that myself and deciding which RAM kit to use. Any suggestions (from vendors)?

 

Funny thing is, if you get Corsair Vengeance RAM, it doesn't have an XMP profile, even though the ram is expensive.

But there is a good guide on how to add the profile:
http://forum.notebookreview.com/har...orsair-vengeance-cpu-z-jedec-screenshots.html

 

So basically go with the Corsair Vengeance then? That was my first pick actually. If what you're telling me is that I can end up having 1866mhz RAM by tweaking some software then i'm willing to give it a shot. I think I can manage to do it for the performance increase on top of all ready great RAM.

Thanks for all the great info!

 

Should be able to, but thaiphoon burner does cost money.

 

To be honest, unless the 1866MHz is comparable cost-wise to the 1333/1600 (i.e. < $50) it's not worth it. Only case where it would be beneficial would be for improved IGP performance, even then the difference between 1600 and 1866 is minor.

 

i will second this...and to further this, there are many people on the alienware forums that report issues running 1866 memory. Seems like 1600 is much more stable.

BUT

OP already has ddr3 1333 cas9? Going to 1600 is a waste of cash. You won't notice one bit of difference and you might see 1-2% on a benchmark

 

I third this. Spending extra money on 1600mhz ram sticks isn't worth it, the only improvement you will see is probably 1-2% increase in ram benchmarks, the performance gain will be miniscule at best.

In real world usage, there is absolutely no way you will perceive any kind of difference by going from 1333 to 1600.

 

I have corsair-vengeance 1600 ram and it has two profiles in the BIOS.

 

From my understading with benchmarks out there even going to Z79 chipset and quad channel memory does little, IE the 3820 compared to a Z68 based 2700K. Apparently these are not performance bound to the memory speed.

 

Thanks for all the input guys. I figured the performance gain would not be drastic, minimal at best. However, I went ahead and purchased the Corsair Vengeance RAM. Curiosity got the best of me I guess. I rely on the iGPU for everything so any increase in performance there is welcomed.

I am selling my G.SKILL 8GB sticks in order to recover some of the funds spent on the Corsair's. I will buy Taiphoon Burner later as I am interested in testing the possibility of OC'ing the RAM to 1866MHz. If it doesn't work well, then 1600MHz is where they'll stay.

 

To put it in plain English.

If you already have PC3-10600 then if you add in PC3-12800, which is supported by select 2nd generation mobile Sandybridge CPU's (of specifically their memory controller) then your laptop will still run the RAM at 1333MHz effective. Only if you install PC3-12800 exclusively will it resort to working at 1600MHz.

Furthermore, always choose memory frequency over timings as this simple rule of thumb will offer more performance. Only buy in to lower timings if the price is right as the differences in speed will be 1-4%, i.e. something you won't even notice.

Last but not least, when given a choice of memory frequency, timings and capacity always go capacity, frequency and then timings, in that order.

Corsair and G.skill don't make the RAM chips, they fabricate them by buying in from those who do and sticking their own logos on, speed binning, marketing and so forth. For this reason just so with the best deal and after sales support. RAM is a very competitive market so they should all be bending over backwards to please customers.

 

I changed over to the Corsair Vengeance and sure enough out of the box the RAM was clocked at 800MHz (1600), even with my i7-2620M. I didn't think it would work because according to the Intel's ARK page, this CPU only supports up to 1333 memory.

I ran into this over at Newegg:

Newegg.com - G.SKILL 8GB (2 x 4GB) 204-Pin DDR3 SO-DIMM DDR3 1600 (PC3 12800) Laptop Memory Model F3-12800CL9D-8GBSQ


"Keith
12/16/2011 3:21:42 PM
Tech Level:
Ownership:
Verified Owner
Works Great - Lenovo T420 Sandy Bridge
Pros: Works out of the box. Runs at DDR 1600 on the Lenovo T420 i7. Yes, it does run at DDR 1600 on the i7-2640M, despite what the intel webpage says about that processor.

Core i7-2640M Sandy Bridge. CPU-Z reports all JEDEC Values as advertised. 800MHz 9-9-9-27-39.

There's a JDEC for 977MHz at 11-11-11-33-48 for anyone that adventurous.

Type: DDR3 - Channels # Dual - Size 8192 MBytes - DRAM Frequency 797.6MHz - etc, etc, etc.

Cons: Didn't come with nano-bots to install itself for me.

Other Thoughts: Confirmed speed with MaxxMEM2"


I then went ahead and bought Thaiphoon Burner Super Blaster - Professional Edition (7.4.0.3 Build 0212), downloaded it and managed to write the missing XMP profiles onto the Corsair Vengeance timings chart. I successfully added an Enthusiast (DDR3-1866) and Extreme (DDR3-2133) profile. But for some reason only the 1866 profile can be utilized. This could be due to my CPU, my motherboard, or maybe my BIOS. Im not sure.

Using several applications like MemTest+ 4.20 and HWiNFO64 I was able to confirm that the timings and overall clocks did change. I am now successfully using "1866 ram". I will post some benchmarks and my general findings a little later.

 

I do know that some laptops have stability issues with 1866MHz RAM, so you do need to be careful with that. I'm at 8GB 1600MHz RAM myself, at 9/9/9/24.

I don't see myself upgrading between now and my Haswell laptop again unless I can get 1866MHz, 16GB, 1.35v RAM in the next year or so at a decent price, as I figure it would take all three of those differences to make it worth it.

 

I agree with you. I will keep an eye out for any problems like BSODs.

I noticed Minecraft has gotten very smooth. I usually see 30-50 fps all the time now, even online. Im also using Java 7 Run Time. Can't wait to get my 2820qm in there!

 

Sure you have benefit with integrated GPU Intel HD. He question is how big. What was your frame rate before on Minecraft?
Also you better check how hot RAM is. it is OCed RAM after all.