Switched cpu's, now my system wont boot

demetrius202

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Jan 15, 2011
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I'm building my second rig, and using the cpu from my first rig since it's still good (i7 2600K). I put in this plus switched the ssd to a bigger one and now my old rig wont boot up past the POST and the red light DRAM LED is on. I need this old one to work since my wife will be using it. I pushed the memOK but still wont boot past it, as if now my system doesn't like my ram. The fans turn on, my HDD spins, but the red light stays on and I cant get to the BIOS even. Tried doing one stick of RAM at a time, took out the battery to reset the CMOS, and nothing works. Here's the caveat: 2 yrs ago when I first built this rig, I had issues with the POST (but I don't remember if it was the ram light or something else) and couldnt it out and ended up taking it to Best Buy which fixed it but they were all cloak and dagger about how they fixed it. Last year I noticed that my ram sticks aren't on the qualified vendors list to my mobo but since it had been working great for a year I didn't change anything on it. The old rig has the following components:

cpu: i5 3550p (downgraded from i7 2600K which is going into my new rig)
mobo: ASUS p8p67 pro
RAM: 8 gb (4gb x 2) G. Skills Ripjaw ddr3 1600 MHz
SSD: OCZ Now 256 GB (upgraded from 60gb, old ssd is backed up on HDD)
HDD: 1 TB Western DIgital

My ram worked with my old system settings, why not now? I'm prepared to get new ram at my local hardware store and follow the qualified vendors list but I want to know is there something I'm missing? Why would a different cpu just not be compatible with the same ram?