My motherboard is this one: http://www.gigabyte.com/products/product-page.aspx?pid=...
And i recently replaced my E6420 with an E8400. It says the cpu is not OFFICIALLY supported. After booting up the PC i immediately opened "cpu-z" to see what it's reading. It showed the cpu at it's normal FSB of 1333, 6mb mem etc. Only the clock itself seemed to be 2,66ghz instead of 3ghz. After about 5-10 seconds a pop up appeared "for changes to take effect you must restart your computer" or something along those lines. So i clicked restart and that's when the PC didn't boot anymore. There was no beep, only a continuously blinking red indicator light on the front of the case. Tried reconnecting just about everything on the motherboard - still the same problem. After i replaced the CPU with my old e6420 again everything is running fine. Also, my motherboard rev is 3,3.(says so on the motherboard) though cpu-z reads it like it's 2.0 for some reason. And after reading the 2.0's manual i found out it supports the same cpu, but only with overclocking, which i don't understand... what would i have to overclock? The core speed or something? Another thing, my REV of the motherboard only supports these types of processors (FSB 1333) only with it's latest versions of BIOS. I can't find any info on my current BIOS version on the pc and i don't know how to find it. I tried using the @bios tool to update my bios like the instruction manual says, but once i clicked the "live update" button like 10 seconds later a pop up appeared saying "you already have the latest BIOS version". Oh, one other thing, i also used my old stock cpu cooler which is actually meant for a 2,66ghz processor, seeing as the 3ghz one i bought doesn't use more power or have higher voltage. CPU-z showed it running stable at a an even slightly lower temp than my old cpu (around 38C) so i don't think that could be the problem.
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