I sort of regard replacing hard drives like changing oil in a car – something you need to do to keep things working. It might last, but it probably won’t.

So along those lines, I’ve just replaced the hard drive in my MacBook Pro with a new SSD – my local computer store had two 512GB OCZ Agility 4’s for a very good price – so I got that.

One things I was worried about was how it works with the crazy NVidia MCP79 SATA interface in these.. they are a SATA-II controller, and have a bit of a bug, where if they see a SATA-III device, it goes “wtf is this?” and clocks it down to SATA-I speed, instead of SATA-II. For hard drives, that doesn’t matter – but for SSD’s, it’s going to limit performance. I have an SSD in my work MacBook Pro, of a similar vintage, and it only runs at SATA-I speed, and it’s good enough, but not great.

I did some reading on OCZ’s offerings – for their “3” series of drives, there’s a utility you can download to set them to SATA-II, but no such utility exists for the “4” series. Well, turns out what I had seen suggested is the case – they will detect they’re connected to an MCP79, and automatically claim to be SATA-II. This is the main reason I’m posting this – in case someone else has similar concerns ;) So this SSD is doing 208MB/sec write, 250MB/sec read, which is pretty impressive.

As a side note: I saw a storage company’s SEs who I work quite closely with while I was buying this – and made a joke about how much cheaper they were than their SSD’s ;)