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goofyrebel

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Sep 17, 2007
so according to the OC guide, its best to increase FSB rather than the multiplier when overclocking. but it also says that by increasing the FSB, ur also overclocking the rest of the system, "including RAM"...so how can u achieve a true 1:1 ratio if your increasing your FSB to match your RAM (without touching the RAM)? seems like ur runnin in circles trying to catch ur tail
 
With Intel processors, the multiplier is locked upwards (can't raise it above default), so you have no choice except to O/C by raising FSB. Using the 1:1 memory ratio just means the RAM frequency is the same as the FSB. So, you buy RAM that is fast enough to handle your overclocking goal. For example, you have an E6850 and want to O/C it from default 333 FSB to 400 FSB. You get PC2-6400 RAM and then 400 FSB puts the RAM right at DDR2-800 (400X2).
 
i get that much, and that is in fact what i plan to do but on an E6550, the problem i'm thinking about is that by overclocking my FSB from 333 to 400, the guide says that will also overclock my DDR2-800 RAM (doesnt say by how much) to what can be assumed 400+ which means my 400 FSB no longer matches my 400+ RAM. mebe it overclocks the RAM by an insignificant amount to really change the 1:1 ratio and i'm just reading too far into it, but i do wonder if it has been thought of
 
The E6550 has a fairly low multiplier (7X), so to get a good O/C you might have to raise the FSB higher than other processors. But, if we use that same 400 FSB example, the CPU clock speed is 2.8 gig and the memory frequency is 400 MHz, assuming we are using the 1:1 memory ratio. To calculate DDR2 speed, you need to double the memory frequency, so 400 FSB at 1:1 is DDR2-800.

Ok, let's say you do that and you are happy, at first. But, later you get better cooling and more overclocking experience and your best buddy is bragging and laughing that his rig is overclocked to 3 gig which is faster than yours. Now you want to go faster. Just like processors, most good quality RAM will overclock by a good margin, especially if you feed them a little higher voltage. Might also need to relax timings a little too. So you bump up memory voltage to 2.2v and raise vcore a little and discover with your new and improved cooling that you can run 450 FSB. That's 3.15 gig and DDR2-900 RAM speed. Lots of RAM, like for example Crucial Ballistix PC2-6400 or G. Skill PC2-6400 that is CAS4 will easily overclock to those speeds. Or, you can just get RAM rated PC2-8500 (DDR2-1066).

Hope that helps.
 
thanks. this helped me also. But say the motherboard puts my crucial ballistix ddr2 800 ram at 1.8v default. will I have to touch this with a fsb of 400? or do i just have to start upping the voltage once i go past what my ram can handle?? is that correct? so i keep it at 1.8v, until i want to do for example 420fsb, then i up it to 1.9-2.0v right?
 
thanks. this helped me also. But say the motherboard puts my crucial ballistix ddr2 800 ram at 1.8v default. will I have to touch this with a fsb of 400? or do i just have to start upping the voltage once i go past what my ram can handle?? is that correct? so i keep it at 1.8v, until i want to do for example 420fsb, then i up it to 1.9-2.0v right?

I always like minimizing all voltages as much as I can as long as it is stable because it reduces heat in your system and room. But then again I am obsessed because I have poor ventilation in my room. But the actual voltages that it needs will be dependent on the RAM itself. Just test it out at different voltages and check stability with Memtest86+ or if you are lazy or don't really care about it just set it to the manufacturing specs and be done with it. My OCZ is rated 2.2V but I could run them at 1.8V with only 2GB and now with 4GB I Just run it at 2.0V.
 
^ok that makes sense. So if it comes at 1.8v for me i will just leave it unless if i HAVE to up it. If my system fails prime 95, how will i know if it is because of my ram volts, or because of my vcore. How can you tell?? cause it could still pass mem test right? or would it show up on memtest???

THANKS engineer, your my hero
 
I've seen lots of people having trouble overclocking Ballistix with low voltage. Ballistix PC2-6400 is rated by Crucial at 2.2v. Can you use lower voltage? Maybe or maybe not. Crucial loves voltage though and I'd give 'em more than 1.8v. Try 2.0v as a compromise. I've been running my Ballistix at 2.2v for months. But, I do have good case ventilation too. Shhh, I've benched them for short periods of time at 2.45v.
 
^ok that makes sense. So if it comes at 1.8v for me i will just leave it unless if i HAVE to up it. If my system fails prime 95, how will i know if it is because of my ram volts, or because of my vcore. How can you tell?? cause it could still pass mem test right? or would it show up on memtest???

THANKS engineer, your my hero

Well batboy has more experience with this RAM so I would try that 2.0V that he recommended and you can test it with Memtest86 (my favorite) or Prime95 has an option too for stressing RAM instead of so much cpu.
 
Obviously this is with high voltage, but maybe it'll show you what Ballistix is capable of when you feed it some extra volts.

Ballistix+3-3-3-6.JPG
 
good god. That's scary, 2.45? =| I killed a set of OCZ by going 2.35 lol. Free replacement though =)

And those are some unbelievable timings.... good lord. 3-3-3-9... .... 1T?! lol impressive at 1T or 2t good lord, still staring at it lol.
 
Actually, it's 3-3-3-6. I use active cooling when I bench at high voltage. Heck, back in the DDR days, I ran BH5 RAM at 3.2v.

EDIT: I tried 450 FSB, but couldn't get it stable. But, 440 worked.

Ballistix-440+3-3-3-6.JPG
 
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I stand corrected... and yet even more impressive *waves white flag* I surrender lol, crazy clock.
 
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