Ram Support for the Motherboard.

therock003

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I need to ask a simple (for you) questions which seems to keep bothering me. Whenever i check a boards specifications, i seem to encounter an (oc) parenthesis under tha last frequency of the ram which supports.

i.e DDR3 1066/1333/1600(O/C)

or DDR3 1333/1600/1800/2000oc

How foes that translate? That in order to support 1600 Ram bust be overclocked? Or that it supports an overclocked RAM module? This thing keeps confusing me, can someone dumb it down for me?
 

theAnimal

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The OC means that you will manually need to change the RAM settings in order to run at that speed. Generally the only reason to get faster RAM is if you are planning a serious OC on your CPU, since OCing the RAM does very little for performance.
 

therock003

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How do you mean? For example if you insert a 1600 RAM module into that mobo, at which speed will it function, without having to manually change anything.
 
First of all, you didn't specify the motherboard.

If we assume the X58 (Core i7) then the answer is 1066MHz but overclockable to 1333MHz.

If we assume an AM3 board with DDR3 then unregistered RAM might be 1333MHz. If your motherboard supports 1600MHz AND it's recognized then you'll get 1600MHz. If it's not recognized you'll need to set it manually, though BIOS settings sometimes add support for newer RAM so you can use auto mode again.

I notice they sell 2000MHz RAM for Core i7 and I can't find any mention of how to use it unless you are massively overclocking your system in an insane way. This does not occur to be the case, it seems more likely that the memory controller and CPU core speed can be independently adjusted. If so, I just can't see a Core i7 920 needing the 2000MHz memory. It's really confusing even to an Electronics Technician like myself. It's easy to understand if I stumble across a good article but I haven't yet.

2000MHz can be supported normally on certain AMD setups. The AMD Phenom II X4 955 supports up to 2000MHz (the memory controller is on the CPU). The motherboard must also support this otherwise it will be downclocked.

A Core i7 setup uses three sticks and most everything else is dual memory support. The overall memory bandwidth for Core i7 is impressive but it boils down to whether you need it or not. Memory bandwidth limitations only usually come into play when the CPU has all the cores maxed out such as when compressing or transcoding.

It's difficult to show a difference between 1066MHz and 1600MHz in most usage, and likely never for any current video game.
 

Rookski

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Will the ASUS M4A79T Deluxe Motherboard support 2000mhz RAM with a Phenon II 955 BE Processor? Will I have to change any BIOS settings to allow it? If so what are they?

Thanks
 
This motherboard has full support for this CPU. Some motherboards require a BIOS update to recognize new CPU's in which case they must already have an existing CPU to do so. After such a BIOS flash they would then insert the new CPU which would be automatically recognized, no setting changes required.

Again, according to ASUS full AM3 CPU support is there already.

RAM:
Any DDR3 set will work. However, you may not be able to attain 2000MHz. According to Asus this motherboard supports an overclock of up to 1600MHz. If the price isn't much difference 2000MHz RAM is fine to buy. If there's a significant difference, get the 1600MHz.

For most things, such as games it's difficult to be limited by your memory bandwidth. This only tends to occur in specific situations such as using all four of the CPU's cores at 100% and even then it may only occur under a CPU overclock. Basically, it's not an issue for most people and likely never for a gamer.

Summary:
Yes, everything's fine. I'd get 1600MHz DDR3 if the price is significantly cheaper. Read reviews, not all RAM's the same. Always err on the side of quality, not the highest speed (which you likely can't utilize anyway).

FYI, you should be getting 2x2GB of DDR3. Any more is a waste without a specific need like editing massive Photoshop files. You can find exensive benchmarks and discussions on this but basically 4GB is optimal. You can always add in another 2x2GB if things change in the future.
 
Hi,
First of all, you are hijacking this thread but since it's so old I'll respond. It needs to be closed.

If you went to your motherboard website you'd notice it lists up to 1866MHz RAM. Let's be clear, ANY DDR3 RAM will work in general, more specifically:

1. The motherboard BIOS contains PROFILES for RAM. Ideally what you do is go into the BIOS and set the profile to "XMP" or whatever and the proper timings and frequency will be applied. Compare these to the values listed for your RAM.

2. You can purchase higher frequency than what you motherboard supports but that's really a waste of money. It will work likely, though. Although, I have seen 2133MHz DDR3 work in motherboards listed to 1866MHz so I'm not sure what's up with that.

3. For best compatibility purchase RAM that is on the LIST of approved RAM for your motherboard. Your support site should have a list. It may not be up to date though.

4. I believe you can overclock the RAM beyond the top limit. In general, I don't recommend that. Use the "XMP" profile for best compatibility

Other tips:
1. 8GB is ideal for gaming. More is a waste (needed only for video editing and similar tasks).

2. In some cases 2133MHz is better than 1600MHz for gaming but that's rare. You'll also need a fast CPU similar to an i5-3570K to take advantage. If in doubt spend a little more on 1866 or 2133MHz RAM. To be clear, 2133MHz vs 1600MHz MAY provide a benefit in some games depending on the game and your other hardware whereas 16GB vs 8GB will provide ZERO BENEFIT. ZERO.

3. Don't forget to flash your BIOS to the latest as well as your important motherboard drivers (Intel can even scan and recommend updated drivers but in general go to your motherboard support site).

4. run MEMTEST ( www.memtest.org ). Errors indicate either bad RAM or incorrect settings (hence using the profile). Most errors pop up in one minute. You should run a two-hour test at least once. If you see any errors, test your RAM one stick at a time. See your motherboard manual as you can't choose just any slot (same goes for two stick).

5. If you use 8GB, use two slots. If you use 16GB it doesn't matter too much, however 4GB modules may be cheaper than 8GB modules (again 16GB is overkill for gaming only).