P4B266 FSB Question

[rgowen]

I am assuming that if your fsb is above 133, then the PCI is fsb divided by 4 and the AGP would be half the fsb. Is this correct? Just curious because it would seem if that is the case, then Turbo 1 would really not be needed until you get over 145 since at 145 you would have 36.25/72.5 PCI/AGP and Turbo 1 is suppose to run at around the same numbers. Just wondering because I just upped my fsb to 145 and left the setting at Normal instead of Turbo 1 and left all voltages at default and it seems stable so far even after some Prime95 action.

 

[Rickard]

I think that is correct yes.

 

[huck328]

Wllh the P4B266, are the AGP and PCI slots automatically adjusted down to 66/33 when fsb is 133 if you use Normal mode, or only under Turbo 1?

I was up until 2am last night trying to figure out why I couldn't hit anything over 105 fsb (including 133) until I took out my Linksys Lan/DSL card (while using Normal). When I took that card out, the board ran 133fsb like a champ. I put it back in and it won't boot past the XP login screen again. I didn't think to try Turbo 1 since I thought that it would just speed things up more. (now I'm at work and can't test it).

I wish there was just an option to set the PCI divider manually in the bios. Is it there, but I'm missing it? I have no idea how that PCI card would crash the system if the PCI slots are Really running at 33mhz when my fsb is 133.

Thanks in advance.

 

[rgowen]

I was able to go up to 150 fsb using Turbo 1 starting at 146 fsb with no USB problems at all with my MS Intellimouse Optical. I was even able to leave the cpu and ram at default voltages. As for the PCI/AGP buses, I think they are only in spec at 100 or 133, everything else puts them out of spec.

 

[huck328]

Just an update in case anyone else has the same problem...

Changing to Turbo 1 did not help. It still immediately locked up with the Linksys Ethernet/LAN card in it at 133 fsb. I went out and bought a new Kingston Ethernet/LAN card tonight and now it works great! I'm at 1.6 x 133 right now, and can't wait to rev it up more.

 

[WarCon]

rgowen, what voltage did you use to get to 150? Just seeing if anyone else is pushing their voltage.

 

[rgowen]

At 150 fsb, I was able to leave the voltages at default for both ram and cpu. I also had the ram set by SPD. I have 2 sticks of 256 Meg Crucial PC2100 DDR. I ran Prime 95 and a bunch of Q3A and Elite Force Benchmarks with no problems. I will be posting all my benchmarks on my website in the next week or so. I ran all my benches at 133, 140, 145, 150. I will probably still run at 100 (both 1:1 and 3:4 mem) and 132 (1:1 and 3:4). I probably can go higher than 150 fsb but have yet to try.