Why is gpu-z the only program that can read my gpu temp?

Whenever i play a game i have to have 2 different programs open on my second moniter (looks messy) . One (system information for windows, i know there are more compact programs, but this one gives me the most readings) and gpu-z. Gpu-z is the only program that i tried that can actually display my gpu temp. I have a laptop so i like to keep track of cpu and gpu temps. My question is why doesn't any other program read my gpu temp. (i tried real temp, siw, and cpuid, and speefan) and is there one program out there that will actually give me every available temp. Rivatuner is out of the question cuase i have a 64-bit vista which enforces signed drivers.... My graphics card is Ati radeon hd 4650 mobility.

I trie it, as a matter of fact i siad it in post. Speedfan only gives me the cpu core temparatures, nothing more. I know the sensors is there becuase gpu-z sees it, but nothing else sees it.