@Axel Vogt

The NAG (_d01ajc) method indeed gives Pi in 15 decimals, the _Dexp just returns the integral again. I tried using the _d01ajc for my 1/sqrt(x) integral but it gives the following error:

Error, (in evalf/int) powering may produce overflow

On my PC they both methods give the right answer.

@acer 

Thank you very much for the replies!

I just looked at the OS of the workplace-PC, so I could compare those, but it's the same OS (3.13.0-49-generic). So it really seems to be a hardware-problem of some kind in combination with Maple 15.

I tried your workaround (evalhf(Digits) = 15 => Digits := 16), but it still just returns the integral on the server.

If you have any other ideas I would love to try them, it's just a weird problem. I will advice the university to start using Maple 2015 but I guess that decision will be made after I finish my thesis.

@acer It's a Xeon CPU (L5640) (24 cores total) if I and lscpu/cpuinfo are correct. The OS is Ubuntu 3.13.0-49-generic. 

The version gives Maple 15.01, X86 64 LINUX, Jun 1 2011, Build ID 635833.

The system(processor) gives 

"Intel(R) Xeon(R) CPU           L5640  @ 2.27GHz" l2cache=-1 prccores=24 prctot=24 mmx no3dnow sse sse2 nosse3 sse4 nohtt

0

Thanks for your time!