Need Some Advice On Purchasing Extra Memory

[Ex_Brit]

I'm looking to increase my DDRAM following the failure of 2 out of 4 512mb KVR333X64C25's, and I thought I'd go for 2 X 1gb to bring my total to 3gb.

Getting rather confused on whether to go for PC2700 as I have now with a CAS Latency of 2.5 or go for the PC3200/400MHz, which only comes with the higher CAS Latency of 3?

Motherboard is Intel D865GBF and have checked that the modules below are all compatible.


KVR333X64C25K2/2G 2GB 333MHz DDR Non-ECC CL2.5 DIMM (Kit of 2) (Approx US $173)

KVR400X64C3AK2/2G 2GB 400MHz DDR Non-ECC CL3 (3-3-3) DIMM (Kit of 2) (Approx US $184)

 

[mqudsi]

Go for the 400MHz, you can easily drop the CAS to 2.5

But you say it only comes in CAS 3?

My 400MHz comes stock at 2.5...... (same mobo as yourself)

However first try running your remaining two at 400MHz - if you can't (mobo refuses to boot), then it won't matter, because you can only run it at the lowest common denominator, if you understand what I'm saying.

 

[Ex_Brit]

All of Kingston's choices for this M/B in the PC3200/400MHz range were CL3. You don't happen to know the Make/code of yours?

I find it puzzling...400MHz is better than 333MHz but CL2.5 is better than CL3....that's my dilemma, although I know that in a mixture the whole shebang will operate at the speed of the lowest component.

 

[mqudsi]

Exactly.
But MHz matters more than timings if you're going from 333 to 400

But that is all moot depending on your current memory.
Can your current memory run at 400? Try that and lemme know what happens.

 

[Ex_Brit]

From what I've read the D865GBF can't be overclocked. I've been into the BIOS several times and can't get the screen where one does that...it just isn't there.
I could take out the 2 X 512 and just use 2 X 1gb then maybe buy 2 more later on and make it 4gb altogether.

(Groan...I'll have to reactivate Windows...again....!!)

 

[mqudsi]

You can't OC the FSB, but you can OC the memory to an extent.

F2 | Chipset Settings | Advanced | User Defined

 

[Ex_Brit]

It's this page...and the burn in thingy at the bottom that don't come up in my BIOS.
I'll take another look.

 

[mqudsi]

Perfect.

SDRAM Frequency.. just change that to 400

 

[Ex_Brit]

OK altered SDRam Frequency to 400Mhz...now what's going to blow up?

Then what new memory would I buy...the PC 3200/400mhz CL3..?

 

[mqudsi]

If you changed it to 400 and your PC is doing OK and nothing smells like a bomb went off (just kidding!), then go ahead and get the 400MHz memory.

Once you get it try to run everything at 400MHz & 2.5 CAS. It might work. If it doesn't, just switch to 400MHz and 3 CAS - it'll still be faster.

Good luck!

 

[Ex_Brit]

Very dubious about this...LOL Nothing's burning so far and my core temp is around 43°C and holding. I don't have a large number of fans - just the power supply and the cpu. I have the highest possible graphics card before a fan is needed and it does generate a lot of heat, especially as my PC maker put the M/B on the wrong side of the chassis so all cards have to be mounted upside down...LOL. Just worried about anything sizzling.
How can I run it at 2.5 when the card only comes as 3?
The ram I'll buy only comes, as I said, as CL3 unless I forget about the overclocking and settle for the standard I already have PC2700 and CL2.5...the difference isn't much really is it?

 

[mqudsi]

It depends - do you game a lot?

It's perfectly safe - nothing will break. Your mobo will simply not boot, so you just pull out the new memory chips enter the BIOS, reset the memory settings, put them back in, and restart.

I've been doing it for a while with my no-name memory, but Kingston's great, you shouldn't have a problem.

 

[Ex_Brit]

I don't game a lot but when I do it's pretty hectic!! I just feel more comfortable knowing the PC has some breathing room and isn't panting for breath/memory. So how to drop the CL to 2?

 

[mqudsi]

Don't.
Going from 3 or even 2.5 to 2 is really, really hard for your PC.

With memory OCing is really a hit-or-miss kind of thing. If you're lucky, your chip will support it without any issues and with no side-effects - else it just won't OC no matter how hard you try... so I'd say your on the good side

 

[Ex_Brit]

I went back in and saw that I had overlooked those settings

I set SDRAM Timing Control to "User Defined" ("Aggressive" lowered the next figure by 2)
" Ras ACT to Pre "7" (I didn't change it)
" CAS# Latency "2.5" (I didn't change it, but lowest is "2")
" Ras to CAS# Delay "3" (I didn't change)
" Ras Precharge "3" (I didn't change that either)

The question is really is all this worth it...i.e. is that extra 67MHz yet a higher CL worth all this (& a few extra dollars)?

 

[Ex_Brit]

It just occurred to me that the above "User Defined" setting will force the new memory (when I get it) to CL2.5..... maybe I should forget the last bit?

Interesting article here: http://www.andrew.cmu.edu/user/fma/P4tweakRAM2.htm

 

[mqudsi]

Exactly, that's what I was trying to tell you.
The 400MHz in User Defined Settings would force the old memory from 333 to 400, and the 2.5 would force the new memory from 3 to 2.5 - you get the best of both worlds if you get lucky !!!

 

[Ex_Brit]

Thanks...I'll keep my fingers crossed that I don't burn the city to the ground, or something to that effect.

Just kidding. I appreciate your help.

 

[mqudsi]

no problem, best of luck, and keep us posted

 

[Ex_Brit]

One last question...if I ditched all the old RAM and just put 2gbs of new....which one would you choose out of the two? (That way there'd be no need for tweaks).