----i7 860---- Overclocking guidance needed.


I'm new to tom's hardware and new to building and overclocking PCs.

I built a new system in Dec 09 and I'm really pleased with it, but I know with a bit of tuning and overclocking I can make it somewhat better!

This is my system...

i7 860
asus p7p55d motherboard
corsair CMD4GX3M2A1600C8 4GB 1600MHz 2x 2GB RAM kit
nvidia 8600GT 1024MB
2x 500GB Western Digital caviar green 32MB Cache
Win 7 x64 Ultimate Edition

I plan to upgrade my graphics card and double my RAM in the near future.

I want to tune up my system now to get the most out of it. I have been trying to do as much reseach on overclocking before i start so I have as good an idea of what I am doing as possible, however I still have a lot of questions that haven't been answered in any of the articles I have read so I decided it's time to start asking people in the forums!

Okay first things first... I want to use my computer mostly for computing, not games. I mostly use it for a heavy amount of photoshop, Illustrator and web browsing and also some coding of websites and word processing. Also in a year or so I expect I may well get into video editing.

What I have so far learnt is that the type of computing I do is very memory intensive and so therefore I should try to configure my system with this in mind. I have been told that I should try and get the most out of the potential my RAM has to offer.

These are the stats for my RAM...

Fig 1)

Fig 2)

Fig 3)

it is 1600 MHz RAM but I have a couple of queries about it..

1) what is the difference between Real Clock (beign 800MHz) and Effective Clock (being 1600MHz)? is that normal to have a real clock that is half the effective clock? if I only had 400MHz RAM would it's real clock be 200MHz?

2) in Fig 3 it says 'DRAM Slot #1 2GB (DDR3-1333 DDR3 SDRAM)' does this mean that my memory is actually only running at 1333MHz? I read that the maximum speed supported by the intergrated memory controller on the i7 860 processor is 1333. Does this mean that 1333 is the maximum i will ever get out of my memory? Figs 1 & 2 show the memory to be running at 1600MHz (800MHz) so what is the truth? What speed is it actually running at?

Fig 2 shows that my DRAM:FSB ratio is 6:1. This is what I have been told I need to tweek. I've been told I need to get the ratio as close to 1:1 as possible so that there is no redundancy in the speed of my RAM.

As I understand it, anything where the ratio is higher than 1:1 on the DRAM side means there is redundancy in the RAM and it is simply not getting used and so it would acctually make no difference to have RAM with a lower speed as long as you didn't go below a ratio of 1:1. Is that statement correct? can you corroborate this for me? If there is a point to having fast RAM when you don't have a 1:1 DRAM:FSB ratio then please could you explain it too me!

So to get a better DRAM:FSB ratio I hear I need to raise my Base Clock speed. In all of the tutorials for overclocking my processor or or one of the processors in one of the i7 or i5 families the Base Clock has been raised to around 190 - 200 MHz. Raising my BClock to 200MHz would give me a DRAM:FSB ratio of 4:1. That sounds like a good improovement but it's still a long way from the 1:1 ratio I desire.

In none of the overclocking tutorials I have read does it mention anything about why they have settled on this Base Clock. So why have they decided this is the best place to stop raising the BClock and instead raise the multiplyer? They have given no reasoning in any of the tutorials. Is there a danger in raising the BClock higher? or Is it possible to have a really high BClock and a low multiplier? Such as a BClock of 266MHz and a multiplier of just 14 to give a Core Clock speed of around 3.8GHz? A BClock of 266 would give me a DRAM:FSB ratio of 3:1 which is better still.

So what I need to know really is:- Is there a danger in having a very high Base Clock speed?

If there is a danger what is the nature of this danger? Is having a high Base Clock dangerous full stop?

Or is it only dangerous if I want a high Core Clock speed as well ( say 4GHz). I would be happy with only overclocking my Core Clock to 3.4GHZ or 3.8GHz if it means I can get faster memory and overall better system performance.

Or is there no reason why they chose this value to stop at and it was purely arbitrary that they chose 200MHz to stop overclocking the base clock at?

here are a couple more Figs to give you any extra info that may help you help me...

Fig 4

Fig 5

Thank you very much for taking the time to read all of my article.
Any help that you can give is much appreciated!

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  1. I really want to answer your question but its hard when you start off with a wall of text and pics. try focousing your threads with one or two questions so you dont overwhelm people with questions your not gonna get many replies with this wall you posted.

    1) what is the difference between Real Clock (beign 800MHz) and Effective Clock (being 1600MHz)? is that normal to have a real clock that is half the effective clock? if I only had 400MHz RAM would it's real clock be 200MHz?

    A: DDR3 gives a transfer rate of (memory clock rate) × 4 (for bus clock multiplier) × 2 . So 1600 mhz ram will look like this 200x4=800 then its double data rate so your 800mhz bus speeds x2 so 200x4=800x2 gives you an 1600mhz effective memory clock.

    Sorry the rest of your question is hurting my head LOL hope that atleast explains how ddr3 memory works for you.
  2. Thanks for your reply SAAIELLO. Unfortunately I don't really understand your explaination.

    I can appreciate that my post looks quite long, but that is mostly because I have put in 5 screen shots (which can be mostly ignored) if you were to take them out then It would just be considered 'a bit of a long post'. I chose to discuss everything in one post rather than in separate threads as all of the issues are sort of connected. And It seems to me that they aren't issues that are discussed much that could be important in building an optimised system. Anyway enough about the length of my post. Criticising the length of my post is just taking things off topic, and not helping me at all!
  3. I'm kinda with Saaiello on the wall of questions here, but.

    The easiest way to determine your Bclk, vcore, memory speed is just with CPU-Z. Under the memory tab 1/2 of your memory rate will be listed (800=1600).

    Yes, It does look like you are running at DDR3-1333 (and no this isn't the limit), you can go into the Bios and change the ram multiplier so it is running at 1600 if you aren't going to be OCing the cpu. If you are going to be raising the Bclk you will have to adjust your ram to the most appropriate speed after determining what Bclk you will be using.

    As for Bclk, your board will limit how high you can set your Bclk (unless using exotic cooling of some sort), it will be in the 210-220 range. That is why a lot of people settle on 180-200 for their Bclk. The higher you have set your Bclk the higher some of the voltages (like vtt) have to be set to stabilize your system. So yes it's a game of compromise and testing to determine the most effective OC for your system. Example OC: 200X20 = 4.00 Ghz and then you would be able to set the ram at 1600. 180X20 = 3.6 Ghz but your ram would only be at 1440, but it really isn't a big deal because your greatest speed would be from the cpu OC and not much of a difference because of the ram speed.

    Many things to consider that you will learn with time and experience. Just make sure you have a GOOD cpu cooler and monitor your temps and voltages when you decide to OC. Also, download the Intel data sheet so you know all the pertinent max voltages so you don't get into any trouble there.
  4. Thanks for the reply RJR,

    In the bios I have already set the DRAM frequency to 1600MHz so I don't know why it is showing as 1333 in that image.

    here is the cpuz image that shows the memory speed..

    so I guess it is running at 1600MHz, but back to one of my questions, if my FSB : DRAM ratio is 2:12 that means that my memory is running 6 times faster than my FSB so In fact there isn't any point in me having memory any faster than 266MHz which would give me a 1:1 FSB : DRAM ratio anything higher than 266MHz is just being wasted. Is that not true?
  5. Best answer
  6. Thanks for the links RJR.

    I think that tomshardware article is pretty damn conclusive that faster RAM really makes no difference! I'd really like to see another article that keeps the RAM speed and Clock speed variables fixed while changing the base clock and comparing results of different configurations.


    BClock 153MHZ x 26 = 4000MHx

    BClock 189 x 22 = 4000MHz

    BClock 200 x 20 = 4000MHz

    getting exact values is a bit difficult being constricted to using inegers so my figures are approximations.

    What do you think of the idea for this way of benchmarking? being a noob I'm not really confident enough to start experimenting and benchmarking. Do you think tomshardware would consider doing such a test?

    The other link you gave I think I read when I was doing research on which processor to buy, but good to look at none the less!
  7. What software produced the screenshots out of interest?

  8. everest ultimate edition
  9. Best answer selected by CheckMate2010.
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