Installing 512 840 Pro into system with existing HDD + mSata cache

OK - finally got my Alienware M17x. It came with a 750 GB HDD + a 64 GB mSata SSD set up as a cache drive for the 750 GB HDD.

I also now have a Samsung 512 GB 840 Pro SSD that I want to add to the laptop, The plan is that the Windows 7 OS and most programs (not all) will go on the SSD, and the HDD will continue to be used for storage and less critical apps, using the cache drive to speed it up.

I have seen people say you need to set the BIOS to AHCI (before or after you plug in the new SSD?) when installing the SSD. But I was just informed that doing that would then disable the ability of the 64 GB mSATA drive to work as a cache for the 750 GB HDD, as that works via RAID. And I suppose that means (I am REALLY ignorant on drive tech) I can't have those two set up in RAID or whatever to work with each other and the new SSD set up separately in AHCI - i.e. the BIOS can only use one mode for all connected drives.

Also - some have commented on the 840 Pro having issues with RAID?

ANYWAY - if it were you, and you had a new laptop with a 750 GB HDD and 64 GB mSATA cache drive, and installing an additional 512 GB 840 Pro, how would you do it?

Thanks very much.

 

over 100 views and no replies! Either a poorly worded request or just terribly uninteresting.

 

I would never RAID such an expensive SSD with a cheap run of the mill 64gb SSD. Also I don't think its RAID, its the Intel RST caching system. I recommend you disable the cache and use the 64gb SSD as storage for some games alongside your 512gb Samsung Pro. The reason nobody has commented is that nobody has done what you are going to do. I understand that caching is an attractive way to increase the HDD performance but I would be more inclined to use it manually (i.e. having a partial Steam library here).

 

Yeah, I don't really know how the Intel caching system works since my Lenovo uses ExpressCache rather than the Intel "Accelerate" option.

So with that caveat (like, I don't really know for sure), my guess is this: Leave the Raid option enabled in the bios and and just 'Accelerate' the secondary, 750GB HD. AFAIK, just because raid is enabled in the BIOS doesn't mean that you need to need to have your primary SSD in an array. As I understand it, the Intel Caching method uses the raid driver to set up a special raid arrangement between the SSD and the HDD. After you've installed the OS on your primary SSD and installed the Intel drivers, use the Rapid Storage Panel to "Accelerate" the 750GB and *not* your primary SSD.

With my setup, I have a 1TB secondary hardrive that is cached (by ExpressCache) using an mSata 64GB partition and I think it makes a significant difference so I can understand why you want to do what you are talking about. There's been some discussions about this in this forum but I honestly didn't follow it too closely since it didn't apply to my configuration. But I'm pretty sure it's been done.

 

My ignorance is clearly handicapping me here!

What I want - the "what" - is to have the 750 GB HDD in place with the 64 GB mSata cache drive connected to it to speed it up. And the new 512 GB 840 Pro SSD separate as my main working drive.

The "how" is what I am struggling with. One reply suggests that if I leave the system in RAID mode, my 512 GB SSD will be dragged down in performance by the 64 GB mSata cache drive. Is that how it works? Will RAID mean that the 840 Pro and the mSata 64 GB cache drive are connected and thus the 840 Pro's performance will be bottlenecked by the 64 GB cache drive?

In other words, how is the RAID currently set up on the M17x with an HDD and the mSata cache drive (what mode, and what does that mean?) and how will the drives be connected if I leave it in RAID and add the 512 GB 840 Pro?

Thanks.

 

Um, I'd just install the 840 Pro SSD and leave the HDD + mSata SSD alone. If you want to use the 840 Pro as the main drive, go into the BIOS and change the boot order of the drives - simple as that. This will allow you to use the HDD as a storage drive with the mSata to speed up its read/write times.

Edit: If you only have one HDD bay (not including the optical bay), then I'd just use the SSD and forget about the mSata SSD because those are a lot slower and would actually do more harm than good if RAID'ed with the 840 Pro. In other words, I'd remove the HDD + mSata SSD and install the 840 Pro SSD.

Edit 2: Scratch that. You can keep the bios in RAID.

 

No, I have an empty SATA3 bay, so it would be a simple add a new drive, no desire to change the HDD+cache drive set up at all.

But on your point 2 - if I switch the BIOS to AHCI, I lose the HDD+ cache drive combo, right? That can only work if the system is in RAID mode (I think?)

 

You can leave your BIOS in RAID even if you don't have anything in a RAID configuration.

 

Cool. So I guess the question boils down to this: If I have the HDD and mSata cache SSD already on the system, in RAID mode (so the SSD can serve as a cache drive,) and add the new 840 Pro SSD leaving everything in RAID, but don't add the 840 Pro to any RAID array, will it still run in SATA 3/SATA 6Gb/s mode? Even though the existing HDD/cache drive run in SATA 2/SATA 3 Gb/s mode?

 

Yeah, as long as the port is SATA III. Just give it a shot!

 

Yep, I think I have enough info. Time to just install it and see now! (though I leave on a business trip tomorrow so it will be next weekend before I can set it up, argh!)

 

I finally came across this post again - it might help if there are problems:

How to: Set up Intel Smart Response Technology (SSD caching)