Inspiron 1501 doesn't POST, loops

Just been given a free Inspiron 1501 (pretty basic, 14.1" model with a 1.8GHz Mobile Sempron, 60G HDD, 1GB RAM (upgraded to 2 though), that apparently emitted smoke in the past.

Tried it with an identical charger (a HP charger with the same voltage and amp rating), and it powers on, I hear the fan, I hear a whir and 3 very quiet beeps from the ODD, and then it loops and does this again and again. The power light is on, and the charging light is orange, and none of the 4 status lights are on.

Can't give any more information sadly, but does anyone know what might be the culprit? I have other RAM I could try.

 

I think you should try with a genuine Dell adapter. The HP brick might have the same nominal specs, but it doesn't have the ID chip in the Dell adapters, which may or may not be necessary for the thing to work.

If it emitted smoke in the past, though, I'd assume there's something wrong with the motherboard anyway.

 

I tried the RAM in my Toshiba and it didn't boot. One of the sticks of RAM was faulty. However, when I put just the working stick in, the caps lock light flashes. Same happens if I put the RAM from my Toshiba in.

I have tried searching for what the caps lock light flashing means but have got a variety of things from CPU to motherboard to RAM.

According to the people who gave me the machine the smoke came from the top right corner, exactly where the heatsink and fan are. This makes me think the CPU or something in that area is the culprit. I do have a CPU I can put in, an AMD Turion X2 RM-70 (I know the 1501s were sold with some Turion X2 chips, the TL-60 being one of them), but although it will physically fit in the socket, I don't know whether it will work. Any ideas?

EDIT: After applying pressure to a known working DIMM in Slot A, I get a solid caps lock and num lock light. No pressure, Working DIMM in Slot B, I get no error codes at all but no video on either VGA or the screen