View Full Version : Multiplier tinkering with A7N8X..??

12-16-02, 02:47 PM
Hello all,

I recenlty built a new system based on the A7N8X / XP2400+ / PC2700 DDR with the intention of running the FSB at 166 (as opposed to the official 133)...and I read in several reviews and posts that this was a feasible alternative to paying the extra $100 to $200 for a 2600+ or 2700+.

Anyway, I cannot get my board to post whenever I set the multiplier to 12X and 166FSB. I get a black screen, some drive activity and then nothing. If I power down (not reset) and enter BIOS I can get the machine to start up with auto multiplier and 133 FSB. I've locked the AGP bus, so I don't *think* that is the problem.

I'm wondering if there are other documented success stories out there. I'm using the 1001C BIOS that came with the board. I'm assuming (probably the biggest problem) that since I can adjust the multiplier in BIOS that it should actually work.

Is there a BIOS update that I need before this will work? I'm not finished tinkering, but thought I would solicit some opinions...



12-16-02, 03:32 PM
The only nForce2 I know of that allows you to adjust the multiplier of Athlon CPU's (without tampering with the CPU itself) is the EpoX board.

Otherwise, you'll need to get down and dirty with physically unlocking your processor. There are several guides on the net that detail how to do this, but you risk permanently damaging your CPU. Otherwise you're stuck on the default multiplier (15, I think on the 2400+).

12-16-02, 05:05 PM
Hmmmm.... I read this little tid-bit on Anandtech's nforce2 board roundup:

"We were able to reach 185MHz FSB (370MHz DDR) using this conservative overclocking setup. This overclocked FSB frequency is normal compared to the other nForce2 SPP motherboards we've tested here today.

Using a factory locked Athlon XP 2400+ processor, all we had to do was simply lower the CPU multiplier down to 8X and increase the FSB as high as we possibly could without jeopardizing stability and without increasing voltages. This was made possible by a great feature the ASUS A7N8X Deluxe affords (as do all nForce2 motherboards), and that's the ability to adjust the CPU multiplier in the BIOS without having to do physical modification to the CPU. Therefore, all you have to do is install your multiplier-locked Athlon XP CPU into your nForce2 motherboard and voila; you can adjust all the available multipliers to your heart's content. However, make sure you purchase the right type of Athlon XP; only Thoroughbred-B processors have this capability on nForce2 motherboards. You cannot change the multiplier of a locked Palomino or Thoroughbred-A processor in any of the six nForce2 motherboards being reviewed today.

Here is a link to the full article.

It seems as if I should be able to go anywhere with the multiplier without touching the CPU... 2400+ are all Rev B T-breds, right? Maybe I should be posting over on their forum ;)

12-16-02, 06:21 PM
crank the multiplier down more to check if it is holding you back for hitting a fsb of 166...

next, check your ram timings, some ram are picky about it

then take a look at your temps

and what did you lock your agp to?

12-16-02, 07:37 PM
Thanks for the tips...

I haven't tried lowering the multiplier only, and then bringing the FSB up...I think that I'll try that next. I was just thinking it was a multiplier problem.

Temps are very low (33C) according to ASUS Probe - under normal conditions (i.e. non-stressed)

I locked the AGP at 66MHz