So now that the memory is installed, we need to configure it and then benchmark it
To configure it, when we turn on the computer and enter the BIOS. To enter the BIOS, you may need to find the key needed to enter the BIOS in your motherboard manual, though most board need for the delete key to be press, F2 or Escape when you see the BIOS Splash screen.
If you have the splash screen disabled, the message may appear something like this
With the splash screen enabled, you will typically have your motherboard manufactures logo flash quickly, mine looks like this.
Very classy looking if I do say so myself, and I do.
One thing to remember when setting up this memory is that it does have Intel’s XMP 2.0 Profile; in this case it has 2 Profiles.
In this picture, I have XMP Profile 1 set. This sets my memory frequency to 2400,… but wait its 3000Mhz memory. You will notice right below it though it reads “Target Memory Frequency” 3000Mhz, but how do you figure? Well before we find that, notice below that that under “Basic Timing Configuration” the tCL (CAS Latency) to 15, tRCD (Row Address to column Address Delay) to 16, tRP (Row Precharge Time) to 16 and tRAS (Row Active Time) to 39, this is all saved in the XMP Profile, along with the memory voltages.
Some of you may ask, what is an XMP Profile and if I get it, can I cure it? Well, it’s not something you need to cure, but it is something you want.
XMP stands for Extreme Memory Profile and it was developed by Intel and it was developed to enable tested predefined performance tuning of RAM beyond JEDEC SPD standard specifications. These profiles are stored in the SPD of the XMP DIMM and are extracted by the BIOS to tune the memory controller for optimal memory performance. This was originally designed for DDR3, now in DDR4 it is XMP 2.0.
I know, I through a few more acronyms at you, but let me explain.
- tCL (CAS Latency): The top and most important of memory timings. CAS stands for Column Address Strobe and the amount of cycles, or time in cycles between sending and receives commands. The lower the tCL or CAS the better performance.
- tRCD (Row Address to Column Address Delay): The amount of cycles or time in cycles the RAM is issuing active command and read and write commands.
- tRP (Row Precharge Time): Minimum time between active commands and reads and writes of the next bank in the memory module.
- tRAS (Row Active Time): Time between a row being activated by the precharge and then deactived. Once the tRAS has completed, the row can be deactivated. The lower the tRAS the better the performance.
- JEDEC (Joint Electron Device Engineering Council): JEDEC standards are designed to keep manufacturers and specs in sync. Finding RAM for your system is a little hard today, without the JEDEC standards, it would be next to impossible and would lead to memory being more proprietary thus making prices skyrocket.
- SPD (Serial Presence Detect): Information stored in an electrically programmable and erasable memory that is read only.
- DDR (Double Data Rate): Double data rate synchronous random access memory.
- DIMM (Dual in line memory module): A module containing one or several random access memory chips on a circuit board with pins to connect it to the motherboard.
- BCLK (Base Clock): The base frequency of the CPU is running. It is derived by the multiplier of a CPU, in this case 35 times the base clock of 100Mhz for 3500Mhz.
Ok, back to the memory and its configuration. So I left you with the memory frequency, and why would the almighty XMP profile set the frequency so low? That my friends has to done with the BCLK, more commonly referred to as the B Clock. On this Haswell series of processors as well as some previous processors, the base clocks 100Mhz frequency is tied to memory, CPU Core and PCI-E slots, so when you overclock the b clock, you overclock these as well affecting your video card, RAM, CPU, Sound Card and more, be careful with this setting.
In the picture below at the bottom, you can see the BCLK is set to 125. If you start overclocking the BCLK too much you will start having to adjust vcore voltages, cpu voltage, memory voltages and more and passed 125 can be a bit dangerous. Just above that you can see that the CPU cores have been downclocked to 30, so that would be 3000Ghz but that’s the CPU, we don’t want to underclock that. The trick here is that by raising the BCLK frequency to 125Mhz, we have to multiply 30 by 125 which equals 3750Mhz, so actually the CPU has been overclocked just by setting the XMP Profile to profile 1. This also brings the memory frequency to 3000Mhz.
On XMP Profile 2 we can see this approaches things a little differently. This profile bumps up the target frequency to 2667Mhz from Profile 1 but then also tightens the timings a bit, so it’s not at 3000Mhz anymore, maybe the tighter timings help compensate for the lack of frequency.
Then we can see here that the multiplier is still at 38 and the base clock has been lowered to 100Mhz. Hmmm, didn’t I get 3000Mhz RAM here, did I get jipped? Well, there is only 1 way to tell, it’s benchmarking time.
Then also, something very important is that you can verify if your memory is running in Quad Channel using a few different pieces of software, but I will show you inside of CPU-Z.