Strange issue with new bios and sub 7 multipliers

[spirits247]

The beta bios (16th Jan) is excellent but I've noticed a strange issue with it.

Whenever I use a multiplier below 7, memory scores drop by over 60 on average in memtest

This utility is excellent for overclocking because it boots from disk and gives a good indication of stability without corrupting your hard drive.

NB/

Using a Duron 800, max o/c is 1000 stable. Lowest multiplier is 6, so the highest FSB I can use is 6*166.

For instance,

133*7 (933) = 474 MB/S
144*6.5 (936) = 404 MB/S

139*7 (973) = 496 MB/S
162*6 (972) = 453 MB/S

140*7 (980) = 499 MB/S
150*6.5 (975) = 420 MB/S

Therefore even though the new bios resolves my reboot issue at 166FSB, it kills my memory scores because I need to use a multiplier lower than 7 !!!!!.

At the moment, the highest I can run is 7*143 (1001) without killing memory bandwidth using sub 7 multipliers.

After further tests I conclude multipliers above 7 seem unaffected by this strange bug (I think, only tried 7, 7.5 and 8).

This can’t be hard to fix, can it?

[Holst]

Have you checked that 4 bank interleave is enabled ?

[spirits247]

All memory timings set to fastest.

I assumed that interleave stays 4 way at any speed with this new 16th beta bios (including above 144FSB).

This issue also occures at low FSB's as well, should have posted more results as I can see what you're getting at.

130*7 (910) = 462 MB/S
140*6.5 (910) = 392 MB/S

Have the multiplier at 7, everything is fine. Place it at 6-6.5, bang, memory scores tumble. Strange.

[Holst]

Thats certainly strange.

I cant think of any obvious solutions.

Maybee Epox Tech will take a look.


My duron 800 also gave me problems at lower multiplyers, but I assumed that it was due to a chiped core, but that was on 8KHAL00.bin not the new beta.