Locked FSB

[KC]

Hi Guys,
Is it true that some Athlon 1.2 chips have got the FSB locked if the last letter of the chip numbers ends with B.
The reason am asking is that although i can change the clock multipliers of my cpu, my pc will not start if change the FSB ratio from 100 to 133 and i will have to clear cmos to get it working again. The last letter on my chip is B so i was wondering if that is true. If that is the case can it be unlocked and if so how?????
Advise will be very welcome.

Regards:(

[azhari]

The way you can tell if its locked is to look at the L1 bridges on the die. If they have a tiny cut, then the chip is locked.

However, yours is not locked. If you can change the multiplier, then your cpu is not locked. If it was locked, you could only oc by raising the FSB.

The reason you're locking up at 133 FSB can be due to many things, but not a locked CPU. Going from 100 to 133 is a big jump. You may have to do several things to make that setting work, like raising the core voltage, changing bus ratios, maybe lowering the multiplier ...

What you need to do is start raising FSB slowly, a couple of MHz at a time, to find out where you get instability.

I'm sure the more experienced ocers here have more insight and hints for you too.

[KC]

Thanks for the insight but the funny thing is my bios settings only allow a jump from 100 to 133 on the FSB. It does not allow for subtle increase.

[el]

try something like 6x133 for 800 that should work! some chipsets don't like the pci/agp to be out of spec by much so find the point the 1/4 divider is active and set it to that number and you should be fine.

[Bull]

B means the chip was designed for a frontside bus of 100 mhz and C means 133. I know theres a way to get the bus higher maybe another reader knows more about unlocking the bus speed on the chip. i have a Amd 950 that runs 100 mhz and i tried to run it at 133 and it wouldnt post. If you unlock the multiplier on the chip and set it for 133 mhz with a lower multiplier maybe it would work then.

Could you keep me informed at what you find. I havent had the time to experiment any more on the 950.

[killem1x1]

Originally posted by dlind4
B means the chip was designed for a frontside bus of 100 mhz and C means 133. I know theres a way to get the bus higher maybe another reader knows more about unlocking the bus speed on the chip. i have a Amd 950 that runs 100 mhz and i tried to run it at 133 and it wouldnt post. If you unlock the multiplier on the chip and set it for 133 mhz with a lower multiplier maybe it would work then.

Could you keep me informed at what you find. I havent had the time to experiment any more on the 950.

Like azhari stated, the chip is unlocked. There is not a lock for the FSB. Trying a very low multiplier you should be able to run at a 133 fsb.