Upgrading to 8gb - Few Q's

[jestjest]

Hi there. I built this PC around a year ago and it's been doing me fine so far.

M4A785TD-V Evo Asus AM3 Mobo
Phenom II 555 X2 3.2ghz - Unlocked OC'd @ Phenom II B55 X4 3.6ghz
4GB Crucial CT25664BA1339 DDR3 1333mhz Ram 2x 2GB sticks
OCZ Stealthxstream 600w psu
MSI Cyclone 460 GTX
Win7 64 bit


Ok, so my question. I've recently purchased another 2x sticks of the CT25664BA1339 ram. I'm a noob when it comes to fsb/d:ram ratio's and I'm concerned my ram will not run at it's proper speeds when I add the additional 2 chips in. Any idea if it will or not? If not what can I do to get it to run at the proper speed?

 

[Outlander_04]

Put it in , boot the computer

and if its not working then thats the time to start worrying

 

[photonboy]

www.memtest.org

create a boot CD or USB stick, then test your RAM. Major issues usually happen within seconds.

RAM in a system is rarely the bottleneck, but observe the speed in MHz and see if it's what it should be (1600MHz may show as 800MHz because it's dual-channel).

Other:
BIOS updates sometimes contain new RAM profiles. Update your motherboard BIOS if it is not current.

Summary:
If your RAM runs stable for several hours in Memtest, and the frequency is correct there's nothing to worry about. Note that some Motherboards may limit the speed that the RAM can run at.

The program "CPUID" can show some system details, including your RAM frequency and timings (my RAM is running at 1600MHz. in CPUID each stick shows 800MHz and the timings of 7-8-7-24 or similar).

 

[jestjest]

reason I asked is I saw a post where a guy with a similar system said the ram was running at 1000mhz when he put 4 sticks in.

http://forum.crucial.com/t5/Standard-DRAM-Memory/Safe-to-overclock-DDR3-1333-9-9-9-24-to-1066-6-6-6-18-1-5V-AMD/td-p/9919

He said the spu does not support 4 sticks of 1333mhz.

Where could I check if that's the case?

 

[Wolfshadw]

http://www.asus.com/Motherboards/AMD_AM3/M4A785TDV_EVO/#specifications

Your motherboard specifications.

-Wolf sends

 

[jestjest]

http://www.asus.com/Motherboards/AMD_AM3/M4A785TDV_EVO/#specifications

Your motherboard specifications.

-Wolf sends

The issue isn't related to mobo, but rather the cpu apparently.

 

[photonboy]

Just follow my previous advice, specifically:

1) run MEMTEST to ensure stability

2) observe the MHz of each stick in CPUID. It's dual-channel, so if your RAM is capable of running at 1600MHz on your motherboard it will show as 800MHz

3) RAM speed is limited by the speed of the Memory Controller which is either on the motherboard or on the CPU.

Specifically, the motherboard specifications show that, without overclocking you should be getting up to 1066MHz with some CPU's or 1333MHz with different CPU's.

*The bottom line is that your RAM runs stable (Memtest). Again, RAM is rarely a bottleneck. RAM bottlenecks when the CPU is so fast that the RAM can't keep up. I can overclock my i7-860 with all 8 threads running at 4.3GHz at 100% usage using 1600MHz RAM meaning that my RAM is not a bottleneck here.

The above scenario was for video transcoding. Other applications, including games don't come close to using all of a CPU's threads, overclocked at 100%.

So don't worry about RAM speeds, just stability.