Seems good then, not sure how you'd go about RMA the bad ram without a memtest screen, even though I had a screen of memtest failing I didn't even bother in the end, £10 to send it back just wasn't worth it, so I took it as a loss and won't buy OCZ products again as a result.
Not sure about the different voltages of the same type of ram working together well or not - I'd have to assume no, but would be interested to know myself as am going to get an extra 4 gig of the same ram myself pretty soon.
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