Which tool should I trust?

SunnyD

Belgian Waffler
Jan 2, 2001
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www.neftastic.com
I'm playing around with overclocking things, and I'm trying to determine which tool I should be trusting to figure out what speeds everything are running at.

Sempron 64 2800+ (8x multi) - CPU clock at 266MHz * 8 = 2128MHz
nTune says 2136.8 Mhz, CPU-Z says 2171.3 MHz

HT Link - CPU clock 266MHz * 3x Multiplier = 798MHz
nTune says 801.3 MHz, CPU-Z says 814.2 MHz

Memory Clock - CPU clock at 266 MHz * 150MHz divider (3/4?) = 199.5MHz
nTune says 534.2 MHz, CPU-Z says 197.4 MHz

Everything seems plausible, aside from the memory clock, where CPU-Z seems to be a little more sane. However it looks like nTune is taking the CPU clock and multiplying it by 2, but not taking into account the divider. What's weird, at stock, it does take the correct divider into account as with 2 sticks on a sempron it defaults to 166MHz, and nTune shows the correct 333MHz.

Does everything here look right?
 

n7

Elite Member
Jan 4, 2004
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Now i am assuming you have a Sempr0n that runs @ 8x200 default (1600 MHz).

If that's the case, then overclocked speeds would be:
8x266.66 = 2133 MHz

HT Link speeds don't matter.

RAM divider would be 8x200 / 150 = 10.66 rounded up = 11.
8x266.66 = 2133 / 11 = 193.91
IOW, DDR388
 

SunnyD

Belgian Waffler
Jan 2, 2001
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www.neftastic.com
Originally posted by: n7

Now i am assuming you have a Sempr0n that runs @ 8x200 default (1600 MHz).

If that's the case, then overclocked speeds would be:
8x266.66 = 2133 MHz

HT Link speeds don't matter.

RAM divider would be 8x200 / 150 = 10.66 rounded up = 11.
8x266.66 = 2133 / 11 = 193.91
IOW, DDR388

The 150MHz divider is a 3:4 divider - 266 * 0.75 = 199.5MHz. Unless of course I'm mistaken and it doesn't use the reference clock as the base for memory.
 

n7

Elite Member
Jan 4, 2004
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How to calculate RAM dividers for A64 architechture:

(CPU multi x 200) / RAM divider (i.e. 166) = ___(always round this up if not whole number)

CPU multi x HTT / result of initial calculation = actual RAM speed

e.g.
OCed CPU clockspeed / result of the first calculation = actual RAM speed

one full example:

12 x 200 / 166.66 = 14.4 rounded up -> 15

12 x 220 / 15 = 176 aka DDR352