High Temp when Launch MemTest86

[Guest]

Want to know why my old core i5 2400 CPU reach 98-99C when I launch Memtes86 to test my RAM? It constant in that temprature, 97-99C but there's no problem at all. When idle in Windows, I got 30-40C.

 

In my new desktop, when I launch Memtest86, it show only 40-50C.

 

Question are:

1. Why? Is ist because my old CPU dont have thermal paste (at all)? And not installed in a proper case? See image below.

2. Is it bad if I turn my pc on in that level of heat? Because I want to test my RAM again.

3. How many passes needed to know if my RAM bad or not? I used 2 passes before with no error, is it enough? (2x4gb ddr3 1600mhz)