Running out of ideas for the 486
The 486 I was building would be deemed complete. Nevertheless the issue with memory I'm finding to be quite frustrating and I'm running out of ideas.
I recently bought some other RAM to try and get a different result with each set.
With the 30 pin SIMMs I get 3 low beeps, normally suggesting the 64KB memory failure.
The 72 pin Panasonic SIMMs I bought earlier gives me 8 beeps followed by 2 beeps. I don't really see a matching code for that one
The 72 pin IPEX SIMMs I hear nothing at all when the seller claims they were tested working in a AMD 486 machine.
I'm a little confused as to the manual saying it has a Phoenix BIOS, when I see an American Megatrends BIOS chip on the board itself.
I recently bought some other RAM to try and get a different result with each set.
With the 30 pin SIMMs I get 3 low beeps, normally suggesting the 64KB memory failure.
The 72 pin Panasonic SIMMs I bought earlier gives me 8 beeps followed by 2 beeps. I don't really see a matching code for that one
The 72 pin IPEX SIMMs I hear nothing at all when the seller claims they were tested working in a AMD 486 machine.
I'm a little confused as to the manual saying it has a Phoenix BIOS, when I see an American Megatrends BIOS chip on the board itself.
Comments
How many 30pin SIMMs do you have installed when you hear the beep code? Check to see what your board requires when it comes to installing 30-pin SIMMs, i.e. 2x2 matching pairs or 4 matching, etc. I ran into this problem when I installed only 2 SIMMs, when the board required 4.
If you're hearing 8 short beeps, that indicates a defective or missing video adapter. The following 2 short beeps indicate a memory parity error / failure in one of the hardware tests, or it could be a 10 beeps which indicates "CMOS shutdown register read/write error".
Also, if you're getting no response from your system after installing the IPEX SIMMs, it could be incompatible memory? Check to see if they're EDO (If your board does not support it.
It's possible that you have a different board revision than that which is stated in your manual. Do you know what brand and model it is?
I'm starting to think you got a dead motherboard or just having bad luck with memory.
https://winworldpc.com/winboards/viewtopic.php?f=10&t=7588 No, though it was just a matter of working out which relevant beep code list to go by, as they both have separate lists when I did some searching.
It's disappointing considering the time and money spent.
You should always try and pair 72 pin SIMMs - for the same reason - each module represents a portion of the memory bus' width. This is also why DIMMs can be installed singly - the Double part of their name is because a DIMM is effectively two 72 pin SIMMS stuck together.
Also, check that you've got 32bit 72 pin SIMMs, not 36bit or a mismatch, as 36bit modules will only work in a board which uses parity. The only time you can use single 72 pin SIMMs is when the memory controller is able to deal with the mismatch, older PS/1s can do this. Some memory controllers (like the PS/2 Model 90) need paired SIMMs in alternate slots, so if there are four slots, and only two modules, they need to be installed in slots 1 and 3, leaving slots 2 and 4 empty. Not sure if this applies to your scenario but may be worth bearing in mind.