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Question about cpuNB and HT link

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Dooms101

Member
Joined
Dec 28, 2009
Location
under a heatsink
Uhm... so I've read through alot of OC'ing guides for overclocking on AM2/AM2+ boards (like mine), and I was wondering what good NorthBridge and HT frequencies are good and how to get the most out of my system. There's also a few BIOS options that I am not sure what they do exactly.

BIOS options that I don't know:

LDT voltage
cpuNB 7 - shift (in +mv)
cpu vCore 7 - shift
HT width (to options, either 16 up and down, or 8 up and down)

My main goal is to push my processor to the fastest stable clock, and then bring the rest of my components back up, to get a good overall system.

I've read that you have to monitor the cpuNB voltage and frequency as well as the HT link frequency. I have options in my BIOS for the HT freq from: x1 (200 mhz) to x9 (2.6ghz). The fastest I can get my System Bus to is 260mhz with a 2.5 multi (to factor out the CPU), 1:1 DRAM (to factor out ram), and x1 HT (I dunno why, haven't tried it at a higher multi) with 1.23 vNB, and stock voltages every where else.

Here's a data sheet showing various tests, I never touched the LDT voltage, HT link width, cpu vCore 7 - shift, or cpuNB 7 - shift.
datasheet.png
 
HT Link width should be set to 16^16v.

LDT voltage is the HT Link voltage. I'd leave it at Auto or 1.2 (I think is stock?).

Now that I'm looking at your RAM results again there's something odd there. Everything but the ~533 MHz runs are set to CAS 6 (first timing number). If you can run CAS 5 at 533 you might be able to run CAS 4 at 400 - maybe even as high as 470 MHz. I think my Plats went 473 MHz @ CAS 4, but they were DDR2-800CL4 sticks. At the very least yours should be able to run 5-6-6-18 up to 500 MHz or more. Just a thought. ;)


Which motherboard have you got (not in your sig)? I'm not sure I understand the voltage options you're showing ...
 
I only had the super crap timings just so I could see how fast I could get my ram to go, they run perfectly stable with stock timings (5-6-6-18-2T @ 2.13v) at ~1090mhz. I haven't tried pushing them with a 2:1 ratio for DDR2-800... but I'll try that now =)
(which is more preferable latency or speed? especially with DDR3?)

Here's the JEDEC timings on the ram from CPU-z:
sdfl.png


and my motherboard is a JetWay XBLUE-N78V http://www.jetway.com.tw/jw/motherboard_view.asp?productid=524&proname=XBLUE-N78V

Edit: After like 7 hours of testing and running Prime95, I've come up with some super rock solid results:

tempor.png


So I got it to go DDR2-1000mhz (5-5-5-15-26-2T) @ 2.17 vDimm (CPU-z is off on my vDimm and vNB) and 2290mhz NB @ 1.25 vNB

As soon as I get my new cooler, I'll try tightening the timings some more, and start bumping up the multiplier to get a good overall OC, I think I can get 3.5ghz (250mhz x 14). I've also gotten to DDR2-1014mhz (5-5-5-18-26-2T) with a 255mhz bus clock, but I don't think it'll be as stable as 1000mhz.
 
Last edited:
For most programs (large CAD/Photoshop/video encoding files are the exception) tighter timings are better if you can get the speed. DDR2-900CL4 is slgihtly better then DDR2-1066CL5 ...
 
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