Newb ready to do first overclock

I have read through some of the tutorials here and I think I have a decent understanding about how to go about this. However I have already ran into my first question. I am using a EVGA nForce 680i board. If I understand what I have read I should set my FSB – Memory Clock Mode to unlinked so I don't have to worry about ratio between the FSB bus speed and the MEM bus speed. Is that correct?

I went ahead and tried it and noticed the timings have changed when I viewed them using CPU-Z.

Unlinked:
DRAM Freq: 266.7
FSB Dram: 1:1
CL: 4.0
tRCD: 4
tRP: 4
tRAS: 12
tRC: 16
CR: 1T

Before unlink (auto):
DRAM Freq: 400
FSB Dram: 2:3
CL: 5.0
tRCD: 5
tRP: 5
tRAS: 18
tRC: 23
CR: 2T

Should I go back into the bios and change the unlinked settings to match the auto settings? At this point I am not trying to overclock the memory, I just haven't been able to figure out if the memory is underclocked at the current unlinked settings.

System stats:
Intel Core Duo E6600 Conroe
EVGA nForce 680i SLI
Mushkin PC2-6400 (400mhz)

Thanks for any input, its much appreciated.

don't worry about the ram right now. Leaving it unlinked will allow you to find out what your CPU can do without it being a limiting factor.

Thanks for the quik reply I just found out my multiplier has been set on 8 instead of 9 since I owned the computer (6 months or so) lol. Off to experiment...

You should probably leave the mem at Auto, that way as you increase the speed the BIOS will automatically make the transition from 1:1 to 5:4 when it needs to.

That makes sense, I will give it a try. I thought we wanted the 1:1 ratio? Thanks for the help.

I am up to 3.0ghz and haven't had to raise the voltage yet. Still testing how stable it is.

1:1 is ideal, but it puts a lot more stress on the ram. Usually without some tweaking (ie. upping the voltage, playing with the timings) it's hard to keep ram at 1:1 once you get well above it's spec speed.

Thanks for the input. In my bios when I switch it to unlinked the FSB-Mem ratio automatically goes to auto. The only time I can adjust the ratio manually is when I set it to linked, so it appears its all good at the moment. I have it unlinked with ratio on auto. With the CPU at 3.0Ghz the ratio has changed to 5:4

This is fun

Ya 5:4 is perfectly fine.

When I first started overclocking I was given some great advice by a member here (madhyena). When overclocking, especially when dealing with new hardware, or overclocking the first few times in general. You really should only change one thing at a time.

So you don't want to be trying to overclock ram and the cpu at the same time. Take things slow, don't push it yet. Get to a point where you are borderline stable and stress it for a bit with prime 95. Take things slow you don't have to jump to 3ghz+ that first day.

The higher you go the harder it will be to get things stable. You will start dealing with more factors such as temperature.

Have fun and get some nice benchmarks posted

Yes I am taking it slow. I am still at 3.0ghz and never getting over 51c underload. Just trying to see how low a voltage I can get away with. After running the computer at 2.1ghz since I owned it I am quiet happy with 3.0 at the moment. I have tried some various settings with the memory, but haven't noticed any distinct difference. Right now its linked and synced running at 333mhz 1:1 4+4+4+12+16. It has passed all the stability test so far, but I want to do some more.

My best score on 3dMark06 was an 11500. Thats with an 8800gtx, no idea if thats good or not. However before I started overclocking it was an 8900

Well if you are happy with 3.0 you should start working on your memory. It's running a bit slower than stock so you should be able to work it back up to 400mhz.

What you could try, its a bit of a jump, but running a 4:5 divider would put you back at about 415mhz on your ram.

Or, you can write down your cpu settings, where they are. Set it back to stock and just overclock your memory. Find maximums for both and then go from there working on getting them both to their max.

Thanks for the tips, I am planning on trying some stuff today. I realized I was a bit low on the 333mhz but I figured the lower timings would make up for it? I am basing this off of things I have read. I was trying to keep a 1:1 ratio, but I am open to all ideas and plan on trying all sorts of variations.

Well.. Tightening timings up a bit isn't going to make up for a 20% cut in speed.

Most real world applications won't benefit all to much from tigher timings, at least not enough to notice. Now that isn't to say you shouldn't tighten them up a bit. Especially if you are going to be running some benchmarks.

Thanks for the feedback, its much appreciated. I have been toying with different settings all morning. I went back to unlinked 4:5 and 400mhz, set my timings to 4+4+4+12. Slowly starting raising the mhz and it maxed out at 416 anything higher and it wont boot into windows.

I have been using Sandra to benchmark the initial memory changes. When it came to the bandwidth and cache memory test my old settings where just slightly better. (I forgot to mention on the old setting I could get away with running CR @ 1x instead of 2x) However I have better latency scores with the newest settings. When I ran 3dMark I scored a 11631 so that is about 100 better than before (dunno if thats within a margin of error). Of course I haven't ran any significant stability test on it yet.

I am curious if I should explore raising the voltage. I can't seem to find anything on my ram as far as voltage goes except it says its 1.8v I don't know if that is recommended? Minimum? Maximum? I also read a few articles where they raised the timings to get a higher mhz, but this seems counter intuitive to me.

That's probably right around the minimum. Especially if its performance ram. Most of them will tell you speeds, timings and voltages on the sticks.

Some sticks will be 1.8-2.0v stock, others will vary. You of course can go beyond this if you want some serious overclocks. Just take is slow.