Help with low FSB O/C on P5b

OK, I am trying to decide if I have a screwy board and should RMA it. The hightest stable FSB I can run in 355. I have tried the following...
It is stable at 8x355=2840, so I know the processor is good up to there.
I am running Corsair XMS 6400 (2x512) that I have tested up to 830 with no problems.
Dram Frequency 1:1
PCI Express 100
PCI Clock 33.3
Spread Spectrum Disabled
Memory Voltage 2.1
CPU Core voltage 1.5~1.525
FSB Termination Voltage every setting from half way to max
NB Voltage tried em all, no real change
SB Voltage tried em all, no real change
ICH Chipset Voltage yup, once again, tried all combinations

Dropped the multiplier to 6x375 and I get nothing and have to restart. I know the processor will run this speed and it is way under spec for the ram.

Tried the magic 401fsb also. 6x401 gives me nothing but a chance to restart and "overclock failed" message.

All this is running on high end watercooling. My CPU temp in the bios is usually showing around 100F, which seems awful low.

I also connected my second half of my ATX connector on the motherboard by using a line off my Antec SP500 power supply. It is modular so I reconfigured my spare second PCI express video card power cord to work in the extra slots since my almost new power supply lacked an eight plug connector.

So please tell me I am missing something simple. I am real disappointed in this board so far, and I am going to RMA it if I can't figure something out.

Thanks, any suggestions welcome!

check here
http://www.ocforums.com/showthread.php?t=477358
i am trying to put all the data in ONE place.

for your problem i would try manually JUMPER clearing the bios, then reset everything before the first boot.

my PSu only had a 6 pin and a 4pin for the 12V extra connectors, it didnt bother me none.
4pin on the motherboard, with the little CAP still on the other 4
6 pin to the almighty power sucking video card.
ya know its just +12V and Ground going down a bunch of wires.
meaning the redundancy is just to get many wires running the SAME power down there.
potentially there could be just 2 going to each, but by doubling quadrupling and quintupling it, the connectors and the wires and everything can handle more amperage of juice, or even handle poor connections.

hmmm, also the chipset, is being tortured when you overclock, make sure its properly cooling too

Tone your memory timings down a bit, you cant be sure its the CPU that is not handling the overclock, till you underclock or undertime the memory first. the memory can cause a OC failure, and good speedy low timing crucial might have to have more wait states to handle the speeds your trying to reach. if you got 444 move to 666 for a while, apropriatly adjusting the otehr stuff relative to the change your making.or 2/3rds it for a bit, so you can see what really isnt handling the OC.

more info

Thanks for the response. I have tried so many things with this thing and nothing seems to work. Here are a few new one...
I have flashed every BIOS, the 507, 605 and 706. Cleared the CMOS by the jumper. Even read one thread to flash it, clear it, flash it and clear it. Same thing.
Just pulled off my water cooling and put on stock heat sink and fan.
Same thing.
6x358 boots, anything higher and it is reset city...
Couple of other settings I have tried I did not mention above...

Static Read disable
C1E support disabled
max cpuid value limit disabled
vanderpool tech disabled
cpu tm function disabled

I am about out of crap to try with this thing.
One more note, when I very first got it together I did get it to run at 8x401 overnight. Then when I tried restarting it it puked and has never been able to go there again.

Any more ideas? Am I right in thinking this board is badly under achieving?
Thanks for any imput,

you left one off your list

Spread spectrum disable.
its some kinda interearance fixer, and warbles things to reduce interfearnaces, disable for overclocking.

Actually i have all that stuff on, but off would be best for overclocking.
i like the scaling, and LOVE HLT because we didnt have that with AMD , HOT HOT HOT.

i was 100% stable at 370, then put a new heat sync on, and completly reworked the chipset cooler. and magically went to 400.
and heck i was happy at 360 but what is WRONG with 360? does 14% of just the CPU really do squat difference for the overall speed of your computer? i mean your not at 266, BE HAPPY!

got it working finally, but not sure how...

Thanks for the input!
Yes, I have that one off too, hell I have about everything off...
But, I had a breakthrough...don't ask me how, luck I guess...
OK, I read something about another poster having problem with their ati 1900xt. I happened to be building a computer for a friend with a Nvidia 7600GT. Tried it and same damn thing. No suprise, but I like to try everything. Took the 7600 out and put it into the second PCI express slot, set the fsb to 410 and damned if it didn't boot. Multiplier was at 6 so I knew I had some headroom. Ran it up to 450x6fsb at almost stock voltage. Still going, did not try 460, too excited something finally worked...
I have tried 410 repeatedly the past few days and no luck. Not sure why it decided to work now...
OK, here is the weird thing...I had missed setting the Dram frequency to 1:1...I left it at "auto." I tried moving it and as soon as I did it would no longer boot. I slapped my waterblock back on (not easy since it means I had to take the motherboard back out after I had it out earlier switching back to air), cranked up the multiplier and now I am running 8x420=3360 and running nice and stable.
Soooo.....any idea why it insist on "auto" for the DRAM frequency? Oh, and one other thing I pushed the PCI express up to 110. That wasn't intentional, but hey, it works, so I am not screwing with it....

get CPU-Z and find out why auto works.
with cpu-z you will be able to see the timings it is using , and the actual speed it is running at.
look in the MEMORY tabs , and you can see the timings that are in play.
one of the memory tabs shows what the SPD for the chip is, and one will show what its running at for real at the time.

i can imagine what a pain it would be to tear the computer apart, to change the cooler type :-(
that is why a lot of the OC work is being done outside of a case.
but as usual, its ONLY when you put the screws in, do you realise that one last thing that needs to be done.

You indeed should be able to OC the PCI buss too, it was mentined before, that we have been ocing PCI busses since the Old days of overclocking, as it was the ONLY way to overclock when the cpu was locked.
ANY pci card should be able to handle a 10% OC on the pci and it will increase the speed of way more things.
we used to OC them up to 30% , some types of cards would freak out and destroy your data.
remember that having say a SATA running overclocked it only takes 1 piece of data blown out to toast a whole file, or even make a mess of your disk. so have a backup, because if LATER you discover a bunch of bad files, your going to be ticked.
you can imagine if you DEFRAG a disk it messing up just one piece of data a minute , the whole disk would be a mess.
ALSO
some PCI cards used the timing of the buss to time the card, and they would not work in any way shape or form if overclocked, or sounds and video would speed up, or some crasy unexpected thing or error would occur.
BUT
the pci-e is already blasingly fast, and probably more critical, and you might be OCing things like your video communication more than it can handle.
people overclock thier Video as a seperate item, but it does not change the transfer speed of the buss, only the GPU speed, and the speed of the video memory.
sooo, at LEAST test your texture memory sharing, and your video game playing with a 3d bench when you go to do that, so you dont get surprises.

test any firewire junk and any USB stuff, the firewire especially when transferring video wont work with the timing off.
lots of things ON the pci buss are not in any way capable of handling different timings, but that is the whole rest of the computer, and just as important to the real speed of it.

so HECK yes, after you get the CPU peaked, then get the ram peaked, then get the PCI peaked, and just like all the others if you go to high, boom boom out go the lights.

Well, my success was short lived. I ran if for a few hours at 430x8 and it ran perfect. Gamed with it and encoded dvd with it. Then, I tried to install the motherboard monitor software off the Asus disk and it froze. Restarted and it would not boot. Had to back the thing down to 450x6 and it runs fine at 2700mhz. Ran all night without a complaint. One thing I have not tried is running my vcore voltage down. With my watercooling I always run a lot of voltage. I ran 2.1 volts to my barton core Athlon for two years and that never fussed once. So I will try that later, but my cpu temps is very low.

Oh yea, it is a huge pain since my waterblock is not designed for a 775 processor. Well, it wasn't designed for the 939 it spent the last year on either, but it works. The fun is that my radiator, pump and water tank is under my house with copper lines running to rubber lines to the water block. I use a radiator out of a Chevette and two big 110 volt fans. It is completly quiet since it is under my house and cool year round. But it is a major pain to change motherboards on this thing.
I am running the CPU-z program to make sure my multiplier was working. I will have to look at it with respect to my ram timings and try to figure out what is going on.
Oh, I remember overclocking the PCI bus was a huge problem back in the early days...I had the old Celeron 300a with water cooling and a thermoelectric cooler that would form ice on the waterblock if air got to it. Ran that thing at 650mhz and man was it a rocket at the time. PCI was double spec and still hung with me. Can't tell how many times I had to reinstall Windows due to corruption going for 700mhz, but never even came close...
Thanks for the idea on the CPU-z, I will look into that when I get home.

Do you know that you are really running 600fsb. 8/6=1.333x450=600x6=3600.. Edit:that's nb fsb.. http://www.bleedinedge.com/forum/showthread.php?t=23803
Check it out in Sisoft..

Still tinkering

Yup, still tinkering. Latest is running it at 430x7 to get me into the 3000's. Corrupted my Windows install so reinstalling and all is stable for a change.
Yes, I read the thing about how the multiplier affects the FSB on these boards. So, I know I am good up to at least 600mhz is I could ever get ram to hold up that long and put the multiplier up to stock setting of 8.
These things are very strange to get to run well, but I am finally almost happy with it after screwing around for over a week trying to get it to run close to my expectations.

Ya, it took me a 3 day weekend of tweakin' to run pretty good.. And that was before I lapped my ihs.