Memory speed VS CPU

[Sir G]

Hi,

I can imagine you guys see these question a lot, but I couldn't find it in the FAQs..

My desktop has an intel i7-930 processor, and 6GB of OCZ platinum 1600Mhz RAM (3x2GB). The motherboard is an ASUS rampage 3 extreme. Now, I need to upgrade my RAM (I was thinking up to 12GB) since I use the system for simulations which needs a lot of data. I recently have gone out of memory quite a few times, whech causes lots of paging, making my applications creep to a halt.

I noticed that the specifications of the i7-930 say: "Memory Types DDR3-800/1066"
Does this mean the 1600Mhz-capability of the current RAM isn't being used?

I also noticed even the 17-980X doesn't list more than 1066, which puzzles me. Howcome there exists RAM with speeds like 2000mhz? Is it strictly for overclockers? Are there no CPU's that support these speeds out of the box?

Does this mean that I can put 1066mhz ram without any performance loss? (Where I buy them from, this would mean 24GB of RAM would be just a tiny bit more expensive).

I hope you can help me with these questions, much appreciated.

Also for bonus: Is the supported vendor list for a motherboard strict? Let's say I want to by corsair or OCZ RAM, but my specific model isn't in there, but other models of the same speed and brand are. Would it be a problem?

Also, if I buy a 3x2GB set of, let's say, OCZ Obsidian 1600MHZ, could I use them together with the current RAM, or is mixing really not done? I heard advise against this, but I'd like to be sure..

Thanks

 

[o1die]

I mixed ram on my h55 board; you will need to try some manual ram settings in the bios for it to work smoothly. Also use cpuz to see what speed your ram is currently running at. Use more 1600 ram, not 1066. The ram may default to a lower speed if you don't learn how to use the manual settings, but getting the same speed ram is preferable; 1066 was the original ram standard when the x58 boards came out; they can run faster ram on most boards.

 

[Sir G]

I haven't got cpuz, but everest came up with 533Mhz, so 1066Mhz it is.
I'm a RAM-manual-settings-virgin so are there risks involved? I wouldn't want to ruin anything..

Thank you!

 

[o1die]

I still recommend 1600 ram; it's probably cheaper now than the slower stuff. You can get 3x2 gb kits for around $60-75 if you shop around. It won't hurt your board to try the manual ram settings. Just check to see if the ram speed changes when you change a setting before you save and exit. Your board may have numerical numbers or ratios. I use the 5 setting on my msi board and 160 for the cpu fsb, for a decent overclock. But your cpu is different. Before changing settings, find the cmos jumper or motherboard battery, which is usually a round lithium 2032. You can either remove the battery or move the jumper over one pin to reset the bios. Sometimes changing a bios setting will cause the board to fail to post. Then you unplug the power supply in back, and use the cmos jumper or remove the battery for a few seconds (then reinstall) and try posting again. It's not that hard.

 

[Sir G]

You misunderstood me. What I meant was "the RAM is currently operating at 1033Mhz". I'm not planning on buying 1033mhz anymore since you told me about the settings.

My motherboard has all kinds of overclocker-features that I never used, including multiple biosses and recovery and so on, so I'm guessing I would not need to fiddle with the battery in case something goes wrong. I'll look into it.

I am still a bit confused about the CPU-specification saying 1033mhz. I should simple ignore that? Even if I were to install 2133Mhz RAM (which I'm not planning to do, but let's say I would) it would still be able to perform to all it's capabilities by just setting the settings manually?

 

[o1die]

cpu fsb and ram fsb can operate independently of each other using the ram ratios, which can be displayed as 3,4,5 or 1:1.66, for example. Don't try changing the timings, just the ram fsb using the ratio settings. Best to let the board decide what timings to use, especially if you're mixing ram. Hopefully, when you adjust the ram ratio, the new ram speed will be displayed before you "save and exit". Get as close to 1600 as you can; it may not be exact. Could be off a few points and still run fine.

 

[Sir G]

alright, thank you

 

[abdussamad]

My suggestion is to go for 3x4GB of the cheapest branded ddr3 ram you can get. Why waste dimm sockets on 2gb modules?

 

[Sir G]

why not? Unless you would like to upgrade even more later on.. But I'm guessing that when the time comes that I need more than 12 GB of RAM, I'll be using a completely different rig.

 

[jaquith]

R3E's often have problems running RAM >1800 MHz and the errors increase the faster you go on a non-ECC MOBO & CPU.

Until you can get away from using the HDD for 'Memory' it won't make much if any difference running faster RAM. You need to find out EXACTLY 'how much RAM' you actually need to perform your 'simulations.'

Q - What App(s) are you using?

In general, if you cannot escape the 'HDD' then I would strongly recommend that you look at the fastest RevoDrive you can afford.

If 12GB of RAM is indeed enough then to most affordable solution is to purchase a second set of what you already have installed {OCZ platinum 1600Mhz RAM (3x2GB)} AND to properly set the Frequency, CAS and Voltage. Further, ALL i7 9XX have 1066 MHz IMC but can handle up to ~2200 MHz with marginal gains {1066 -> 1600 2-6% depending on the quality of the IC used in the RAM}. In contrast, the SB shows marginal gains above its' 1333 MHz IMC. In my case I 'test' HUGE SQL calcs and the difference between stock 1066 -> properly set 1600 MHz on a 4 hour processing run is 15~20+ minutes.

If your 'simulations' require and will use >12GB then I would sell the current 3X2GB and look for 3X4GB Kit(s).

Since your rig is a Pseudo Workstation, I assume the calculations a not mission critical. Further, your 'simulations' if GPU driven then that too might need to be upgraded; RAM first.