Different Brand RAM and my OC

mischievousape · 03 Aug 2010

Hello :)

I have some OCZ DDR3 Platinum 2x2gb 1333Mhz installed on my Asus M4N98TD at the moment. I also have 2x2GB AData DDR3 1333Mhz RAM stashed away from when I was having some POST problems with this build and wanted new RAM to test.

I've overclocked my AM3 965 to 3.8Ghz.

I tried to add the AData RAM, but I can't get the board to POST. I know I can manually change the timings to be the same, and will have to since the OCZ is CAS 9 and the AData is CAS 9. Using the FSB to overclock affects all the hardware as far as I know, so reducing the OC on the FSB should lead to less stress on the other hardware, allowing the multiplier to OC the CPU alone right?

I was going to use the multiplier more to get to my OC target of 3.8Ghz. at the moment, I increased the mulitplier from stock 17 to 17.5 and the FSB is doing the rest.

If I rely more on the multiplier, and manually force the timings of the RAM, am I likely to get POST with the 8GB of RAM installed? Or should I just leave everything alone and keep the 4GB?

I thought I could get some advice before starting

archie123 · 03 Aug 2010

depending on your bios you can "unlink" your ram , leaving it unnafected (for the most part) by any alterations you make to the FSB , you can manaually set/enter your required ram speed , pay particular attention to your timings make sure you set both types of ram to the lowest sets settings

one thing to consider , some memory controllers go a bit flakey when more then 2 slots are used , you may need to either underclock your ram or up the ddr voltage a little to compensate

mischievousape · 03 Aug 2010

Just about to test this now for stability. But I've got the settings at:

CPU: Multiplier x 18, FSB 211
DRAM Freq 7001.Mhz, Memory Timings 9-9-9-24, Voltage is at 1.80.

Post back after a few hours of some prime system torture

Then I can look at reaching my 4Ghz target :)

Mellon Head · 05 Aug 2010

From experience, I have a couple of tips:

1. It is harder to OC using 8 GB than it is 4 GB, because it stresses the Northbridge. In the end, you'll get a much more stable OC from 4 GB.

2. In most AMD boards, the FSB clock cannot be unlinked from the RAM. However, I had the best success with my old rig by OCing using the FSB (locked multiplier) and setting the RAM divider lower.

3. If you clock your 1333 RAM at 1066, and increase the FSB, you can usually run the RAM with tighter timings, meaning better overall performance than running at 1333 and jacking up the CPU multiplier.

4. You may have to bump up the voltage on your NB, but be careful not to overvolt it. That voltage is applied directly to the Phenom's die, and it will increase the overall heat of the CPU quickly.

5. Try not to exceed the RAM's spec'd voltage. That means don't exceed the max voltage of the lowest voltage pair. You may not be able to get two different brands of memory to OC well if they have different max voltages. OCZ RAM can often take a higher voltage that some lower priced brands.

6. Phenoms are expensive. Just ask my wife. :)