Some hard learned memory facts for you

From- EdWh

Some info I wished I could have found on this forum but did not. Cost me lot of money to learn.

Intel i7 Cpu's and Multi-threading. I found on a long search that disabling the multi-threading when overclocking will reduce the heat load on the top end as much as 10 degrees. Do a search, Asus has as a great article on this and by disabling it causes a 5% loss of efficiency but only on special apps.
Does not effect gaming as I read it.

I also discovered that the XMP program in the Bios only works with memory designed for it. I have 3 HyperX Modules that state they are 1600mhz compatible but this is true only when the XMP is enabled in the Bios. The memory without the Xmp is 640x2=1280mhz tops will not run over that.
The reason is when you begin to overclock the cpu the Xmp goes out the window and you have to DISABLE the Xmp in the Bios to get the machine to post. It will not post with Xmp ENABLED in a Cpu overclock not matter how small. The Xmp program was put in the Bios to allow those who do not want to overclock the Cpu to have a little more efficiency on their machines.

So if you are going to overclock the Cpu forget the HyperX modules they are cheap memory with the program for Xmp only. It is a rip off. to sell more cheap memory at high prices with fancy covers.

I have also discovered that overclocking i7 Cpu's will not normally run stable with memory at 2000 and above so shoot for 1600 to 1800 to keep machine stable, someone could possibly add more to this and I am sure there are exceptions but for us newby's this can save a lot of heartache and money, 2000mhz and above is very expensive.

If anyone wishes to add to this, please do so,we newby's spend a lot of money find these basics that should be a part of this forum and they may be available, but I never found it.

From EdWh. I need to add one more bit of info for you. I bought 12gb Komputerbay memory on ebay and discovered they are labeled incorrectly. They were sold as 16000-2000mhz and are actually 12800. 640mhz x 2 =1280mhz. ebay is helping me for a refund, if you feel you still want to buy, Amazon is Komputerbay official site and they work directly with Komputerbay. There is no direct contact with komputerbay it appears to be a nation out of the US.

Good to know. Sounds like XMP can only overclock RAM in a very limited way.

Question: What mobo are you using? Does it allow you to change any parameters to RAM in the BIOS outside of XMP? Because maybe you just have to search a little deeper to find a path to OC the Hyper Xs

PC3 12800 is the same as ddr3 1600

Also, you should be able to manually switch to the correct speed for your memory in the bios settings without xmp.

From- EdWh.
Hi Janas19 and Xsuperbgx.

The information is made available lto help others, I am still working on a memory to get this board to run memory at 1800 or so.
The Xmp is a Bios insert by Intel that allows a one time overclock of the memory from 1030 or 1600mhz. As soon as over clock of the Cpu is started it throws the Xmp in the Bios out the window and the Xmp in the Bios must be dis-abled or the machine will not post. Please read original post this Xmp memory running as normal will not top 1280mhz. I know I have been trying for days and 1280 is top end. I am workng with Gigabyte to see if I can get a Bios update, so far none of the updates will work with the flash program.
I have a Gigabyte GA-X58-Ud3r rev.2. Which I never would have bought having found out only after I received it that Sata 3 does not work with the Marvel Chip on the board. Gigabyte lied when they advertized that it is Sata 3, you can run on the Intel chipset but only at Sata 2 not three. I spent $200.00 buying 2-1gb Sata 3 Hdd's and they will run only at Sata 2. Again Gigabyte lied, to sell boards. I will never buy another Gigabyie board because of this. They got one sale, but lost a customer. In the meantime am attempting to get a decent speed from the board with overclocking. I am running Cpu at 3.84mhz but memory only runs as stated at 1280mhz.
Stay away from Xmp modules unless you want a one time increase in memory speed with NO Cpu overclock as that is the only mode it is for. Ed.

EdWh said:

Intel i7 Cpu's and Multi-threading. I found on a long search that disabling the multi-threading when overclocking will reduce the heat load on the top end as much as 10 degrees. Do a search, Asus has as a great article on this and by disabling it causes a 5% loss of efficiency but only on special apps.
Does not effect gaming as I read it.

Click to expand...

This is true...and is usually common knowledge.

I also discovered that the XMP program in the Bios only works with memory designed for it. I have 3 HyperX Modules that state they are 1600mhz compatible but this is true only when the XMP is enabled in the Bios. The memory without the Xmp is 640x2=1280mhz tops will not run over that.
The reason is when you begin to overclock the cpu the Xmp goes out the window and you have to DISABLE the Xmp in the Bios to get the machine to post. It will not post with Xmp ENABLED in a Cpu overclock not matter how small. The Xmp program was put in the Bios to allow those who do not want to overclock the Cpu to have a little more efficiency on their machines.

Click to expand...

Usually motherboards, by default will set to DDR3 1333 for compatibility reasons. Normally you either enable XMP profiles to reach those speeds or set it manually (it does NOT require XMP to be enabled). The situation you are describing about the memory posting is due to raising the FSB/bclk/HTT and the speeds are too fast for the system to POST. The XMP profiles are there not for the reason(s) you listed though. Its there to have a profile of its settings.

So if you are going to overclock the Cpu forget the HyperX modules they are cheap memory with the program for Xmp only. It is a rip off. to sell more cheap memory at high prices with fancy covers.

Click to expand...

This advice is situation dependent at best.

I have also discovered that overclocking i7 Cpu's will not normally run stable with memory at 2000 and above so shoot for 1600 to 1800 to keep machine stable, someone could possibly add more to this and I am sure there are exceptions but for us newby's this can save a lot of heartache and money, 2000mhz and above is very expensive.

Click to expand...

Again, situation dependent. Blanket statements like this are not accurate. Most "i7" CPU's (you do know that there are 2 generations of that right? And that the second gen chips EASILY run 2k= speeds. The first gen didnt have any issues with 2k either. It just needs tweaked.

From- EdWh. Hi Earthdog.
Perhaps all this is common knowledge to you but it is not to newby's and that is why I wrote it. I found this knowledge by personal experience and am trying to save other new people the cost that I have incurred. If you know where there are posting other than this one for basic knowledge without having to read 6 pages or more that are difficuilt to understand and quit trying to impress about your guru status.

Most of this information can be found in the overclocking guides for the i series listed in my signature.

I did not mean for that to come off quite like you took it, and I do apologize. The information you provided just needs 'tweaked' a bit for accuracy and its a good post to have...but does need tweaked.

As far as your board and Sata3, there are 8 ports on there, 6 of those are SATA2, the Marvell port are the only 2 SATA3 ports. Its stated clearly on 2their website. Maybe newegg messed it up? Regardless, a mechanical HDD will not show any less performance in Sata2 vs Sata3 so it should be a non issue anyway.

You should change the memory divider if overclocking by raising bclk.
As you raise the bclk it also raises the memory speed. So you need to lower the memory divider or multiplier as required to keep your memory at or below its stable speed. When overclocking I do not leave memory on automatic. That is probably why xmp was an issue for you. XMP likely could not automatically lower the divider or change the divider to avoid the problem. Sometimes increasing memory voltage or loosening memory timings can give you a little more overclocking as well.

xsuperbgx said:

You should change the memory divider if overclocking by raising bclk.
As you raise the bclk it also raises the memory speed. So you need to lower the memory divider or multiplier as required to keep your memory at or below its stable speed. When overclocking I do not leave memory on automatic. That is probably why xmp was an issue for you. XMP likely could not automatically lower the divider or change the divider to avoid the problem. Sometimes increasing memory voltage or loosening memory timings can give you a little more overclocking as well.

Click to expand...

Indeed, the XMP is a profile for the memory at the motherboard stock speed. If you increase the Bclk then you are altering the memory speed. The way I generally use the extended profile settings is as follows. Set mobo to base seeds. Enable whatever XMP profile you are using. Then go to the DRAM configuration page and change from auto to manual timings. This will lock the timings into whatever the XMP requires, then lower the DRAM multiplier and raise the Bclk so that your memory is near its original speeds.

Some hard learned memory facts for you.

Hi Earthdog.

Thanks for the input. Did not mean to jump all over you but seems all guru's forget they were once newbies. Anything I have put out here you can tweak anyway you wish as long as it gives the unlearned basics to those who have to work so hard to get them.

I might suggest that you start a "Brand new to overclocking basic information"
and put in some of the basics to help us get a solid start in overclocking as one of the posts at the home page. Might be a great help.

As for the finding the facts under your previous posts, again I did not even know your name and am not even sure I could bring up all your posts to look at, I do not have that experience. Sorry. Ed.

EarthDog said:

Most of this information can be found in the overclocking guides for the i series listed in my signature.

Click to expand...

Hi Earthdog.
Does your guide apply to the latest incarnation of Intel Processers, Sandy Bridge? Of all the "i" CPUs I see mentioned in your guides, Sandy Bridge is not amongst them.

Not my guides. THe link to SB guide I cannot have in my signature due to site rules. We dont not have a comprehensive SB overclocking guide her at the moment. Just a quick 4.5Ghz one though..

I can link the others with more details below.

1. http://www.techreaction.net/2011/01/04/3-step-overclocking-guide-–-sandy-bridge-v0-1beta/

2. http://www.overclock.net/t/908782/sandy-bridge-overclocking-guide-ocn-members-only

3. http://www.clunk.org.uk/forums/overclocking/39184-p67-sandy-bridge-overclocking-guide-beginners.html