WWYD: replacing sick Mac Pro

[Buzz]

Pretty sure your RAM is fine... IIRC, it's OK to go from quad to hex, the issue may be going the other direction whereupon the higher speed hex spec'ed RAM may be too fast for a quad CPU. IRL it's doubtful you'd be able to tell the difference from RAM speed, because you'd already be so thrilled from the faster CPU and PCIe based SSD you'd also get.
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