My system & I/O voltage : 3.5v wont start, 3.6v unstable... More info inside...

[JustinS]

I bought a 750 SlotA Athlon a couple weeks ago to replace my 500 @ 800. I am lucky enough to be able to run my KX133 based KA7 at the 133mhz FSB, which was the main reason for the 750: 750 x 133 = 1gig. Just a few days ago, I tried to go a little higher, and am running at 1066 stable so far - 8 x 133. 1133 wont boot.

The problem is with my I/O Voltage. 3.3 and 3.4 volts are not enough to start the system. 3.5 volts does not start the system all the time. I may have to do a soft reset a few times to get the system to boot. However once in Windows, the system is perfectly stable. I played a little UT for about 1/2 hour, MW4 for about an hour, and ran 3D Mark 2000 3 times at 640x480 (to stress the system - not the video card).

So, a little recap: 3.3 and 3.4 volts are not enough. 3.5 volts is enough once into Windows.

Next onto 3.6 volts. You'd think that 3.6 would be the perfect setting right? I sure thought so. At 3.6 volts, the system boots every time, but Windows is not stable AT ALL. I have had my system crash on me while I was organizing my start menu!

I have tried adjusting the Cpu Drive Strenght and Pull Up values, but they only make my system less stable.

Anyone else have as much luck as me?

Also, I read that the BIOS version RK fixes this problem from the previous version to that, but I don't know if that fix is still working and my system is just a rare instance, enough to keep the fix from working. I am currently using the official TY bios.

Thanks,
Justin

 

[JustinS]

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[Losty]

I think 3.6 is out of it...
hmmm...
i even think 3.5 is too high...

isn't 1000 good enough?
133 on a kx133? IMPRESSIVE...

 

[JustinS]

I too think 3.6 is a bit much, but before I upgraded my 500 @ 800 was using the 133mhz FSB (133x6) for about 2 months at 3.5 volts without any problems at all. I even had it as high as 139mhz FSB for about a week, but I thought that was pushing my luck.

I thought 1000 was enough, but I didnt buy this 750 just to settle for 1000 . I'm gonna get as much out of this processor as I can.

PS - The 133mhz on my KX133 didn't come that easily. I took me a while, but I managed to find a very thin heatsink and fan (about 9mm thick) to cool down the NorthBridge. It wasn't quite stable without it. A friend of mine can run at the 133 FSB too, as we both bought the KA7 mainboard from the same supplier within a few days of each other. Maybe we just got lucky, and managed to get our chipsets from a really good batch.

Thanks,
Justin

 

[AMDfreak]

My guess is the SB Live! in your system. For some reason it does not like any increases to the I/O voltage at all when used with the KA7/KT7 boards. In my system, I actually had to lower it to 3.2 for stability.