900mhz Tbird @ 133FSB

[Guest]

I'm tring to run my 900 Tbird on a 133FSB with no success what so ever. The computer will gladly POST @ 7*133 but after just a few minutes in Windows or Quake and the system becomes VERY unstable and/or locks up. I know it’s not my ram, which runs fine at 133mhz using a 100mhz FSB. Also the chip will run @ 10.5*100. Any ideas?

Abit KT7A
AMD Tbird 900mhz (Volcano II w/delta 38cfm)
Win98 SE

 

[peteb]

have you tried lowering your memory timing from cl2 to cl3? May still be the RAM.

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[Guest]

What about adjusting the voltage.Thats what I had to do in a similar situation.

Fullspizz People

 

[Guest]

I haven't tried lowering the CL to 3, though I have tried upping the voltage. I also changed the drive strength between the cpu and chipset from 2 to 3 which gave me a little stability but I still get lockups. What should I set the voltage at?

 

[Guest]

Ok I lowered the CL to 3 as well as upped the voltage to 1.8 but it still itsn't working right. Anything else I can do?

 

[peteb]

Hmm,

Where do you make your settings? Jumpers or Bios (I have no exp of Abit boards).

One problem - if your FSB is set on jumper, and your multiplier is set on BIOS, then the initial boot is done at default and the board setting.

Your default multiplier is 9x, even if unlocked, and if the board is hard set to 133FSB by jumper - when the cpu initialises, before bios loads, it will try and run at 133x9 = 1.2Ghz - which may be tough.

I have read that you need to set either all jumper or all bios settings.

Om my Asus board I set the voltage high, and the FSB and Mult low in jumpers, then high in BIOS, which gives it a change to load. Maybe a clue for your Abit - I don't know.

Pete

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[Guest]

With this KT7A all multiplier and FSB settings are in the bios, its a jumper free board. I pulled the chipset heatsink off the motherboard today and Abit only put about half the size of a dime amount of heatsink grease on it. I break out my arctic silver and set it up right. I boot up with my voltage at default, my CPU drive strength at default and my CL at 2. Loaded up some Half-Life and BAM instant lock right as I load a map. I'll raise the voltage and lower the CL and see how it goes.

Also I starting to wonder if it really is my RAM. I am running a 128 stick of Micron ram which is only rated at 100mhz, but if I am using a 100mhz FSB, I can run the ram at 133 2-2-2. You think a true FSB setting of 133, instead of using the HOST CLK + PCI CLK divider is messing it up?

 

[peteb]

Well, a 100FSB, even if RAM timings are set to 133, will not stress RAM IO that much I believe.

Even RAM proven in 1 config might not work in the other. Try and borrow or buy a decent PC133 CL2 stick and see where you go - my bet is still on that, with this information.

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[louie2001]

I have the ASUS A7V133 and 900 T-Bird and I think the 900 is kind of a dud when it comes to overclocking to the extreme.I have generic PC133 and can boot at 7.5x133 or 10.5x100 Can max out core voltage and still no more. I have a 256mb stick of Crucial CAS 2 on the way will see what happens.My highest heat has been 47C on the processor so dont think that is an issue in my case.

Rock out with your AMD out

 

[Guest]

Well one thing about the 900 is the AGGA stepping won't let you go much higher than 1050. I don't think heat is my problem either my full load temp never goes above 45c, its almost always 42c no matter what program I throw at it but sometimes on hot days it will get up to 45c but no higher. I don't really want to go higher than 933; I just want the extra bandwidth that the 133 FSB brings. I can run a 100mhz FSB with the 133 memory divider using CL2, but the 133mhz FSB gives me higher memory bandwidth even when using CL3.

Anyone know the max "safe" I/O voltage? My mobo supports higher I/O voltages I'll try to up that and see what I get.

 

[louie2001]

I can run stable at 7.5x133 but would like more if I can get it most of time I run around 38 to 42 celcius and like you said on real hot days I will reach 47C.Right now with generic ram I lock up if I set BIOS to 2 2 2 on ram then I have to CMOS clear but will run at 3 3 3 so dont know if the new ram will help or not.I like the 133 better than more MHZ.But as usual I need just a little more and more and more (ha ha) never satisfied OH WELL

Rock out with your AMD out

 

[Guest]

You're right on Peteb. I took my I/O voltage up to 3.7 and actually got a semi stable system. I had programs fail but it didn't lock up at all. The only problem with taking the I/O so high is my cpu is running over 50c which I don't like,(I want a computer not a space heater). I'll be looking at some Kingston PC150 in the future, the stuff's really cheap here. I'll see if I can't get the rig to run @ 6*150 or even 7*150, if not I'll be happy with 7*133.

 

[peteb]

Hey - that's great news!

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[Bud]

Dude if ur running pc100 ram with host-clk + pci-clk, that means you're runnring your ram at 133mhz?? 100+33=133. That's the speed the ram clk is set to, it may be too high
for your pc100 ram. Try setting it to just host-clk

I thought I was wrong once, but I was mistaken.

 

[Guest]

If your running a 133mhz FSB it won't let you set the ram speed to 100mhz. The ram runs fine at Host clk + pci clk using a 100mhz FSB because the 133mhz ram divider does not stress the ram's I/O. My origonal question was, Why could my ram run at 133mhz 2-2-2, using a 100mhz FSB and not at all with 133mhz 3-3-3. Thanks to Peteb, I now know my ram won't run on a system with 133mhz FSB because it stresses the I/O to the limit, if I raise the voltage I get a semi stable pc, that just runs too hot.