I bought a used Dell E6500 with an Intel dual core processor (supposedly) but Win 7 Task Manager only finds one core. I've got other computers running dual core and quad core processors, and Performance > CPU history > One Graph per CPU will read as many processors as the processor title says it has. The View menu > CPU history on this new one doesn't give me a choice- only one graph all CPUs. The System description in Win 7 says this is a duo core P8600 processor. I ran Dell Diagnostics on the machine and it says its all hunky dorey, but only reports on Core 0. The CPU performance chart runs right to 100% frequently. But the 6500 machine seems kinda sluggish and its only got an OS on it for 2 days now. The performance rating gives this one a 4.3 with 4.6 calculations per second and 5.5 memory operations per second. Is it possible that one of the cores on the "Intel Core 2 duo CPU P8600" isn't able to run? Is the calculation algorithm accurate in testing CPU speed for BOTH cores? Is there any setting that disables one core? I can't find anything in BIOS that I would suspect that would do that. Or, shall I just check into the funny farm? Yes, I am untrusting--its a character trait. Any help is appreciated.