modify memory timings

I am just preparing to buy ; I am not experienced - sorry for asking silly.
In my ignorance, a change from 10-10-10-27 to 8-8-8-24
seems a major one (even with the provision of using them at lower freq.

I have to choose 2 x 4 GB with 8-8-8-24 at 1600 MHz ; or this Mushkin kit, but I do not fully know if latency question is so important / modules could be forced to comply to better timing

Emma

I wonder if the size of RAM is enough
mainboard I chose has integrated graphic chip -- AMD 880G / I think will use part of RAM
If the 2 x 8 GB could be forced to better timing : might compensate the loss toward shared video RAM

As far as I understand, the memory I was looking to buy is slow.
In your oppinion, is it better to stay with 2x4 GB = 8 GB, 8-8-8-24 than the memory that I was looking (that has 10-10-10-27 latency, but is double the size) ?
Is (2 x 4 GB = 8 GB) - 1 GB shared for video = 7 GB : enough for usual, everyday user ?

I red the articles you suggested, but seems that I need to read more things on this subject.
Thank you for your kind help, I will choose to buy less memory, but with better latency figures.

Emma

6 August 2013 15:46:22
Sorry for bothering you ; the system I started to build is not fully functional yet. Memory that you suggested are OK.
I have problems with keyboard and with shared memory size -- I hope you can help me again.

After installing Win7-Sp1/64 : system offered me highest resolution 1440 pixel ; I would need 1920.
I downloaded from MB manufacturer (ASUS) the driver for on-board video (integrated in chipset 880G -- the integrated GPU is ATI 4250).

The application automatically took control over some 3 GB system memory, from a total of 8 GB.
I do not play games and I do not want so much system memory to be at the video chip disposal.
I tried to go trough the settings of the CCC named application ; I was not able to find anything that would do the setting -- and the "drivers" required about 150 MB on drive.
My previous PC had 1 GB memory on the AGP video card -- it was enough ; I would like to be able to set it to this size, if there is any solution.

I would be thankful for your kind help,
Emma



Updated info 01 May 2014

PC is working well -- it proved that 8 GB memory is more than enough for the tasks I need.
The memory I chose was : 2 x Kingston KHX1866C9D3/4GX in a set.
Dimensions : 132 mm x 41,4 mm ; heat spreader total height 46,41mm ; widt 8,60 mm
Even with memory relatively low-height, it was not easy to install the processor radiator and the fan.
The first bank (slot) would have not been usable with the chosen memory / fan combination -- so filling the 4 banks would have not been possible.
The blue memory banks (slots) would have been better to use (at least this is stated somewhere on forums) ; I had to use the black ones
It was quite difficult to start main-board as the PS2 keyboard was not accepted.
After renouncing to the very good PS2 keyboard in favor of a USB one, I found that BIOS was not associated automatically the processor and memory speeds. For me, it was very strenuous to solve : several problems were present simultaneously and was difficult to figure them out and solve them.
After some use, I made changes in BIOS regarding memory timing, improving a little more the performance.
kept Working 1,65 V = normal
CAS# Latency (CL) = 9
RAS# to CAS# Delay (tRCD) = 11
RAS# Precharge (tRP) = 9
Cycle Time (tRAS) = 24
Bank Cycle Time (tRC) = 40
Command Rate = 1T

After some serious doubts and measurements of power drawn from the source (an older one 400 W, meant for previous generation power requirements), I installed a simple graphic card (Radeon HD 5500, DDR3 1024 MB (800 MHz) Gigabyte) -- and disabled the on-board graphic (integrated in the North Bridge).