Dell XPS 700 Motherboard Issue (DIMMs 1 & 3 don't work)

​Hello,​

​I parted out a fully functional Dell XPS 700 on Ebay a couple months ago, and the motherboard was returned for DOA (the serial numbers matched the one that I sold so it was legit). It was working flawlessly before I mailed it sigh :(. I contacted the buyer after I refunded the money, and asked him iabout some of the symptoms that the motherboard was exhibiting. He said it would power on, but then would blue screen. This happened a couple times he said, and then he couldn't get it to boot up anymore. I immediately was concerned that the buyer fried the motherboard with a bad PSU.​

​Anyways, I have another Dell XPS 700 that works perfectly, and I took the good motherboard out, and replaced it with the one that was returned. After turning it on the power button is solid green, and the diagnostic lights 3 & 4 are lit up. A beep code also sounded in the pattern of 1-3-2. I looked up both the diagnostic light code and the beep code, and based upon what I read it seemed that I had a memory problem. At this point in time, all four DIMMs were filled four 1gb PC5300 sticks of RAM that were being used on the good motherboard (all the RAM has tested good). I pulled out all the RAM, and reseated the sticks, and I still got the same error messages. I then removed all the RAM except for DIMM 1 and still no dice. However, when I removed the stick from DIMM 1 and installed that stick in DIMM 2 the system booted up without issue. I then tried 2 & 3 at the same time and the system will not boot. However, the system will boot again when using slots 2 & 4. ​

​I have come to the conclusion that DIMMs 1 & 3 are not working. Is there anything that I can do to fix the problem, or are these slots just toast? I cleared the CMOS battery and used the jumper, and the problem remains. I also get an error about a floppy drive, which is weird because I don't have one installed. I saw something in the bios about an on board floppy? Anyways, I don't know what the floppy problem is all about, but I just thought that I would mention it.​

​Thanks​

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