Memory Leak?

Hi,


One of our clients is reporting a memory leak in one of our winforms application.
I asked them how they came to that conclusion and they gave me a print screen of their task manager with the .NET application process at 400mb.

Now my questions is .. Is that task manager (Win2k Server SP4) a valid tool in detecting application memory consumption?
Is that manager accurate in reporting the actual memory foot print?

I ask because I used perfmon to monitor the application as well. I used the 2 counters, Total Reserved Bytes and Total Commited bytes under .NET CLR Memory for my application instance. But both the values of the perf counters do not match that of task manager. In fact it is alot less!

1/. Can some one explain to me how I can get an accurate real time memory usage of my .NET winforms app?

2/. Can some one explain the differences in the 2 perf counters I am using, the Reserved Byte and Committed Bytes counter?



Thanks
Jim