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8rda+ checksum error and no keyboard

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Timmybighands

Member
Joined
Jun 2, 2003
8RDA+ checksum error


I have the same problem as a few other guys. I read their posts, and tried the same fixes, but no luck.

Same thing everytime - after IDE drives are detected, it displays "CMOS checksum error - defaults loaded", and it wants me to press F1 to continue or delete to enter setup... but my keyboard doesn't work. Post code 7F is displayed, which means it's waiting for me to press F1. Again, no keyboard. No keyboard lights...

I tried reseating the cmos jumper, I made sure it was on right, EVERYTHING. Driving me nuts.

Any info you can offer would be nice. Thanks!
 
Okaaaaay... I removed one of the memory sticks, and the thing works. What the heck?

Also, is this an official 400FSB Board? Just curios :) I've got a 3000+ 400fsb, and when I put THAT in, it says I got a bad O/C and I need to reset CMOS.

Thanks guys!
 
Are you depending on defaults set automatically by your BIOS?

A lot of RMAs are caused by 'BIOS traps', such as:
1) BIOS assigns default Vcore too low for stable CPU operation.
2) BIOS reads 'SPD' chip(s) on memory and assigns memory frequency and/or memory timings that are unstable.
3) Both above.

Learn how to manage your BIOS.

Spend some time mapping your CPU, memory and board limits, using manual settings. Use asynchronous operation for testing, if necessary.

You can determine CPU FSB limits by running memory asynchronously at 60% of FSB, lower if necessary, and incrementing FSB, adjusting Vcore as necessary, until you reach an FSB frequency where you just can't stabilize the CPU, regardless of Vcore. Prime95 is useful for qualifying CPU 'stability'.

You can determine memory speed and timing limits by using 5X multiplier and running memory at 120% of FSB, using Memtest86, incrementing FSB, and noting memory frequency when Memtest produces errors. You can save testing time by using Memtest Test#5 only, since it is the most critical test.

You can get a rough estimate of board/NB FSB limits by combining 5X multiplier and memory frequency of 60% of FSB. This is only an estimate, since the NB will be working much harder at real-world multiplier settings and 100% memory speed - but it'll be pretty close. Use Prime95 for judging 'stability'.

In other words, use your BIOS, don't be abused by your BIOS.

Hope this helps!
 
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