OC easier with less MEM - why?

[VulkanBros]

I have done som initial/basic OCing ..... and a thing is jumping in my eyes....
I can get a higher OC with 2 x 2 GB mem than with 4 x 4 or 8 x 8 GB .... why is that so?

Or is it alone a question Corsair vs. Kingston?

I have tried various configurations (multiplier, voltages, timings and so on.....) and everytime the low mem config wins..........



Specs:
FX 4100 BE (AMD)
KÜHLER H2O 920 (Antec)
Crosshair IV Formula (BIOS 3027 BETA)(ASUS)
4x4 GB DDR3 1600 MHz Venegance (Corsair)
2x2 GB DDR3 1600 MHz HyperX Genesis (Kingston)
Vertex3 120 GB (OCZ)
GTX580 GV-N580UD-15I (Gigabyte)
TruePower Quattro 1000 W (Antec)

With 2x2 GB HyperX I can reach 4.45 GHz (19 x 235 @ 1.49v) MEM (1567MHz)

With 2x4 GB Venegance I only can 4 GHz (18.5 x 221 @ 1.52v) MEM (1473 MHz)

 

[EarthDog]

Thats an easy one . Less stress on the IMC (Integrated Memory Controller).

 

[VulkanBros]

Thats an easy one . Less stress on the IMC (Integrated Memory Controller).

That would mean 2x1 GB would be the best config for OCing the CPU......hmmmm a shame I dont have 2x1 GB mem

The IMC is integrated in the CPU - so the CPU is the weak point in my config.....

 

[PaulieG]

Thats an easy one . Less stress on the IMC (Integrated Memory Controller).

This. However, I was impressed with Sandy Bridge in this aspect. There was less disparity between 8GB and 16GB overclocks than I expected.

 

[VulkanBros]

Well.......the next processor will have to be Intel I think......
And for the record - Sandy and Ivy they also have the memory controller integrated?

 

[BarbaricSoul]

so the CPU is the weak point in my config.....

Of course, it's a bulldozer








*runs away laughing I'm sorry, couldn't resist.

 

[BarbaricSoul]

Well.......the next processor will have to be Intel I think......
And for the record - Sandy and Ivy they also have the memory controller integrated?

Honestly, unless you really need the extra power of SB or IB, keep what you have. You have already spent the money, it not like your 4100 is really a bad CPU, it just not as good as SB or IB.

 

[cadaveca]

Well.......the next processor will have to be Intel I think......
And for the record - Sandy and Ivy they also have the memory controller integrated?

Both AMD and Intel have intergrated memory controllers on all current products. Intel also has integrated PCIe controllers on the CPU. It's not just about memory control however, cache plays it's role as well, and very few apps out there actually test CPU cache, so few have explored this. However, this is much more evident with SB-E chips, where how a SB-E clocks memory is also related in a large way to how the CPU core clocks, too.

AMD memory controllers, really, are only meant to run 1600 MHz. 1866 MHz with 2 DIMMs only(which, technically, is an overclock when using 4 sticks).

 

[VulkanBros]

Of course, it's a bulldozer


*runs away laughing I'm sorry, couldn't resist.

In everyday work and gaming it runs just fine......it´s only when I tease it
with a little juice and squeeze it a little that it becomes a pain.....

It would be cheap´er just to stop playing around with these things......

then again...that would be boring

 

[BarbaricSoul]

well like I said in my "serious" post, it's not a bad CPU, it's just not as good as Intel's new generation quads. Persoanlly, if I already had all that, I'd look for a 8 core if I was to replace that quad.

 

[VulkanBros]

well like I said in my "serious" post, it's not a bad CPU, it's just not as good as Intel's new generation quads. Persoanlly, if I already had all that, I'd look for a 8 core if I was to replace that quad.

I got it - but seriously - the 8 core AMD (also Bulldozer I would assume) are as bad as the quads ..... so I would have to go the Intel way.....and that kind of money I dont have.....

Maybe I should go for Opetron´s ......

 

[erocker]

Why not just bump up the CPU/NB voltage (which is the memory controller) and get things more stable at higher clocks?

 

[VulkanBros]

Why not just bump up the CPU/NB voltage (which is the memory controller) and get things more stable at higher clocks?

Have tried bumping up both CPU and NB voltage, by 0.05 steps.....but when I reach 1.24v on the NB the system will not start up.....then I go back to 1.15v ......

On CPU side - 1.38v to 1.45v - but that does not make much of a difference......

OC takes a serious amount of time.....

I have been testing since 07:00 AM this morning till now (that´s 17 hours....shit.....should get me a life instead ... hehe)

 

[Jeffredo]

Why not just bump up the CPU/NB voltage (which is the memory controller) and get things more stable at higher clocks?

Say if you had all four DIMM slots populated and on an AMD motherboard (with a 2000 Mhz CPU/NB) would OCing the CPU/NB make up for the extra RAM being there? In other words, if I was intending to OC only using the CPU multiplier would bumping the CPU/NB 200-400 Mhz help compensate for all four DIMMs being filled?

Reason I ask is I upgraded to Win 7 last fall and filled all four slots (4x2GB) before I heard that having more than two filled would hurt OCing.

 

[cadaveca]

It doesn't really affect clocking THAT much. Maybe a couple hundred MHz at most, and that's a big maybe.

Clocking up the NB will help in performance, as the CPU_NB speed also kinda dictates the speed the memory controller runs at too., but the effects are similar to moving from say 1333 MHz ram up to 1866 MHz. Phenom chips seem to be good up to about 2800 MHz at the CPU_NB on average, with some chips going higher. FX chips don't seem to like much over 2600 MHz for 24/7 clocking(going subzero is a different story).


If you haven't clocked up the CPU_NB, you really should give it a try.