Different RAM at same settings possible?

jamesgoss

jamesgoss

jamesgoss

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I've got my CPU overclock sorted out, and now it's time for the dark art of RAM settings:D

I have:

2 x 1 GB Corsair ddr2 800 C4 4-4-4-12 1t

2 x 1 GB Corsair ddr2 800 C5 5-5-5-12 1t

My Asus mobo hates 4 sticks anywhere near 800MHz, so I was running it at 667 to keep it stable. Would it be possible to get the C5 RAM to run the same timings as the C4? Or would I have to run it at the slower timings?

And how high do you think my RAM could go past 800MHz? I'd rather overclock it than underclock it.

Thanks!
 
You "might" get away with running C4 timings on the C5, but you better memtest it, it the ram was from a known good batch, Corsair would have rated it C4 themselves.

However, because your running at 667, then the odds are in your favour that you should at least try using the tighter timings. Tight timings and moderate clocks, can in many cases match the performance of higher clocks with slack timings.

More volts is normally the solution to 4 sticks not running at full speed, but you may need to up the voltage of the northbridge /mch as well, just make any changes in baby steps, you dont wanna fry the northbridge.
 
You would be lucky to run the lower rated kit at CAS 4. You might get away with 5-4-4-12. But before you sit through endless bluescreens and orthos tests, why not just get a 4gig 8500 kit?

What is the rated VDIMM for each kit? you might drop lucky if the CAS 5 kit has a slightly lower VDIMM because it means you could overvolt just that kit and try to get it to match the CAS 4 kit. If it was the other way round E.G. the CAS 5 kit needed 2.1v but the CAS 4 kit needed 1.8v then you have had it really!

jamesgoss said:
My Asus mobo hates 4 sticks anywhere near 800MHz
Click to expand...

Increasing the northbridge voltage might help you here
 
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Ah, well the C4 kit is suposed to run at 2.1v, and the C5 one I'm not sure, as it didn't say on it, though I believe it's 1.8 or 1.9v, having had a look at the 6400 C5 sticks for sale online at the moment.

So I may well be able to overvolt the C5 kit, but the question is by how much? Would I be able to get away with 2.1, or should I undervolt the C4 kit slightly and overvolt the C5 to match? At 2.0v, for example?

The reason I'd rather muck about with this is I have the 4 sticks, I'd rather attempt getting these to work rather than losing money on selling them and re-buying. Though I will if I have to :cool:

mame, how come 5-4-4-12 would work, by only changing the first timing? Forgive my ignorance, it's all smoke amd mirrors for me!
 
CAS (column array strobe) is the hardest timing to lower but the biggest impact on performance.

If thats true that the CAS 4 kit is 2.1 and the CAS 5 kit is 1.8-1.9v then thats perfect for giving it a go because at 2.1v (I take it you know all 4 sticks will always run at the same VDIMM) your CAS4 kit will be using standard voltage and your CAS 5 kit will be overvolted.
 
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Good news all round! Thanks for that. I'll give it a go when I've got access to my PC again on Monday. Hopefully the overvolt will allow me to run the sticks at 800MHz too, and if not, maybe a NB tweak.

I'm used to VCore changes affecting CPU temps, how much would a minimal NB volt change the NB temp? I can't be bothered with active cooling for it, so would quite like it to stay less-than-toasty!
 
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