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Tools for testing would include
CPU: Aida64 (as you mentioned) for a stresstest, Cinebench for a benchmark
GPU: Furmark if you absolutely need to know the max temp for a GPU or want to see if it is stable.. But I don't recommend it anymore, I would much rather recommend any of the 3DMark benchmarks (Steam's demo version does all you need for basic testing - it's a GPU and CPU gaming benchmark)
HDD/SSD: CrystalDiskMark. Nothing really special to say about it, other than it tests your drive.
Userbenchmark is actually quite decent in packing all these sorts of benchmarks together, but take the results compared to other similar systems with a grain of salt.
I have just kind of seen that some of the results in the Userbenchmark database are kinda wacky. As in sometimes the numbers are just way too low, which may be indicative of the user running other software while doing the test, which of course lowers the score..
Stresstest vs. Benchmark:
A stresstest is there to.. Stress the PC and see if it is stable in the 'worst conditions', while a benchmark more closely evaluates performance in more realistic scenarios. They both have a place in troubleshooting, depending on what you need to test.
Depends what you are after. HWiNFO is for checking every spec possible. But if you need to do stress testing, test drive speeds or view drive usage in more detail, you need other tools. HWiNFO is the one to be used for temps, voltages, usage % etc.