Mezpin

Here's a fun one.

I have a 1.4 GHz/266MHz Athlon running on an ABit KT7A. It really HATES running at 133/266MHz. It totally runs like a champ at any speed with 100MHz FSB, but kick it up to 133MHz and it can barely boot up. Funny thing is that even if I tone down the speed to the 800MHz range, it'll still crash at 133MHz, even though I can run 1.3GHz at 100MHz.

First suspect: memory. I had 3 generic 256MB PC133 modules. I tried them in every order and one at a time and nothing could stabilize the system. So I decided that it was time to ditch my memory (something I had been thinking of doing) and I bought 3 x 256MB PC133 CL2 Crucial DIMMs. I still have the exact same problem.

I've tried upping my voltages a bit, both core and I/O but neither seem to help (not too willing to crank them up more than a couple notches).

My CPU consistently runs in the 50-55C temperature range, but that's whether its running 100 or 133MHz, so I don't think it's CPU heat.

I've upgraded to the latest BIOS and all my BIOS settings are at their most conservative aside from the memory speed. 10.5 x 133MHz is what I'm trying to run. My last resort is taking off the CPU fan and taking a good look at my processor to make sure they sent me the right one (ie not a 100MHz chip) but I'm a bit reluctant since the heatsink is such a bitch to put back on.

Any ideas? I'd really appreciate any help I can get.

Mezpin

Oh yeah. I have an ASUS V7100 GeForce2 MX video card, SB Live Value, Adaptec 2906, 3Com modem, and 3Com NIC in my slots. 300W PS. IBM 75GXP 15GB HD and a Maxtor 13GB. Hitachi DVD and a Plextor SCSI CDRW. I dunno if any of that helps.

coleslaw

Try removing all extra components not needed to boot to see if you can start your system with a 133 FSB. If you can, replace the components one by one to see if you can find one that does not like running on a 133 FSB. If your system doesn't even boot with an FSB of 133 stripped down to the bare essentials, your video card may be the culprit. Best of luck!

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Memo

I have read around places that hinted at this being a chipset problem. I have a A7V133 and experience the same damn thing. I can't run at 133/266 Mhz BUS AT ALL. Just simply doesn't work eventhough my chip is an Athlon-C and my ram is PC133. However, I can tone down the BUS to 100 Mhz and run chip at 1.44 Ghz (Keep in mind, this is an AXIA 1 ghz). My first impression was ram also. I tried 4 different ram modules on it, still no go. The best I could do was slightly step up the BUS in increment of 1 Mhz to see where it crapped out. I believe I got it to about 118 Mhz before it wouldn't POST. I'm not sure how the BIOS on the KT7A but you can try increasing the BUS speeds and see where it goes bad. 118 Mhz is better than 100 Mhz, right?

Mezpin

Would it be the video card if it can function fine at 100MHz? The AGP bus speed stays constant at 66MHz doesn't it? For that matter, the PCI bus stays at a constant 33MHz. It strikes me as odd that the FSB speed would affect it, but will do. Thanks.

Mezpin

Mezpin

I have another KT7A back at home that runs 1.2GHz/100MHz. But I run the RAM at FSB+PCI, so the memory bus runs rock solid at 133MHz with cheap RAM. I dunno if anything would change if the FSB ran at 133MHz too.

Will try stepping up the speed too. I did it with the cheap RAM, but it became unstable under 110MHz. Maybe Micron will treat me better.

Mezpin

Mezpin

I fixed my problem! There's a new beta BIOS update for the KT7A which fixes memory problems and allows a 133MHz FSB. I installed it and my system runs like a champ at 1.4GHz/133MHz. I've been up for 3 hours now... typically I couldn't even get 3 minutes. So I'm happy. Though it looks like I didn't need the Crucial memory. Hehe. At least I've got some nice sticks in my rig now.

Mezpin

coleslaw

I'm glad you fixed your problem!!

Also, you can't go wrong with crucial!!

I have a 1.4 GHz Athlon and an Epox 8K7A motherboard sitting here waiting on a home... I can't wait to see what kind of problems I encounter trying to reach 1.7 GHz. hehe