ram go missing after few minitues

[king_solomon]

i got a ddr pc-2700 SpecTek memory which go missing after few minitus, i thing heat is the problem, it runs perfectly for few minits, i even run memtest on it which coms 100% ok. what shoud i do and what is acusing this.

 

[Kari]

run memtest86+ for several hours, leave it running overnight if possible.

But I have never heard that ram could go 'missing' like that, beats me...