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poisondartfrog47
06-08-2015, 03:23 AM
I've read comments by several individuals on several forums around the internet that drive bay 1 is SATA 3, drive bay
2 (HDD) is SATA 2 and drive bay 3 (ODD:Optical Drive) is SATA 1. This does not make sense to me but maybe it's
just me. Anyway, I'm wondering if anyone here knows if this is correct or incorrect? I'm inclined to assume that all
3 drive bays are SATA 3...especially since this would be the most advantageous from a functionality standpoint
(Speed). I'd be inclined to believe that having:

Drive bay 1: SATA III
Drive bay 2: SATA II
Drive bay 3: SATA I

would create a serious data bottleneck. Why not just make all 3 drive bays SATA III ? The big question for me is

Are all 3 drive bay SATA ports compatible with port multiplier adapter cards (Adapter card which allows 2 drives to
be used with [raid 0, 1, SPAN, default raid off] over a single SATA port). Any adapter card, such as EX: promise PCI
raid adapter card, which has multiple SATA ports that allow the user to connect multiple drives through the same
pci port.

In other words, can I successfully use a dual SATA drive adapter card w/ raid (Two Drives Connected To Each Port)
with each of the single SATA ports in the Asus G751JY DH72X? Anyone out there with the answer to my question?

joshindaphils
06-08-2015, 03:58 AM
Where do you envision putting a port multiplier? There isn't exactly a lot of room available.

In RAID 0 (a.k.a a spanned volume) you would be no better off then using the SATA III and SATA II ports as they are in a RAID configuration. If you split a SATA III port you still only have the aggregated bandwidth of the single SATA III port.

If you do shoehorn in a splitter with RAID 1 (a.k.a a mirror) there would be a benefit. Likewise a JBOD (Just a Bunch Of Disk a.k.a. RAID off) configuration would be of some benefit as you would gain speed when only a singly disk is active, but I don't think you will find something that will easily integrate... otherwise I would foresee no issues, good luck on your endeavor.

I would forewarn that the quality of RAID on these devices is likely lackluster, i.e. no trim support, cache, and so on.

poisondartfrog47
06-10-2015, 06:06 AM
Where do you envision putting a port multiplier? There isn't exactly a lot of room available.

In RAID 0 (a.k.a a spanned volume) you would be no better off then using the SATA III and SATA II ports as they are in a RAID configuration. If you split a SATA III port you still only have the aggregated bandwidth of the single SATA III port.

If you do shoehorn in a splitter with RAID 1 (a.k.a a mirror) there would be a benefit. Likewise a JBOD (Just a Bunch Of Disk a.k.a. RAID off) configuration would be of some benefit as you would gain speed when only a singly disk is active, but I don't think you will find something that will easily integrate... otherwise I would foresee no issues, good luck on your endeavor.

I would forewarn that the quality of RAID on these devices is likely lackluster, i.e. no trim support, cache, and so on.


Hey joshindaphils,

I don't intend on using a raid setting but it's always a option. I'm planning on using two ssd with each single
sata port. I read somewhere that in order to do this the SATA port must be port multiplier compatible. I'm not
familiar with port multiplier but I know that you can buy them online. I think the individual mentioned this because
the raid adapter cards need to be connected to a SATA port that is port multiplier compatible or else the single
SATA connection won't be able to handle 2 single drives connected at the same time. I'm not so much
worried about the speed as I'm trying to increase capacity to allow for mobile large file storage. I'd prefer
to buy an inexpensive portable 5TB mobile HDD since there have been so many cheap offers online since
Memorial day but I'm paralyzed and I get around with my laptop on my lap so I need all the expanded
storage memory incorporated into my laptop. Carrying around extra assessories is not an option. The
8 cell battery is bad enough...I wish Asus had incorporated the battery into the laptop.

In terms of space for incorporating the adapter cards....all I have to do is fill the space underneath the adapter
card with some heat resistant foam. A small bit of jury rigging is always needed when attempting to upgrade
computers especially when the manufacturer goes out of its way to design their computers to keep
modders from upgrading said computers. But I say where there is a will and a bit of ingenuity there is a way.

joshindaphils
06-10-2015, 09:22 AM
If speed is not an issue then check out my thread here: https://rog.asus.com/forum/showthread.php?58104-How-to-add-a-4th-drive-to-your-G751

Page 4 has a good example of mounting a 1TB alongside the M.2, a post from user xdr. This is the method I would use for longer drives.

No need for a port splitter, just leverage the ports already provided. You could go all out with 512GB M.2, 1TB SSD in optical bay caddy, 1TB SSD shared with M.2 bay, and 1TB SSD in the HDD bay. 3.5TB should be ample mobile storage hehe. You could eclipse 5TB by using 2TB HDDs in the optical and HDD bays, 4TB spinning and 1.5TB SSD.

poisondartfrog47
06-15-2015, 01:55 AM
I'm in the process of adding a dual adapter card to each of the 3 bays. I've also been able to leave the 500GB m.2
ssd installed while adding a dual adapter card to bay 1. I did have to remove the ssd at first in order to remove the
metal pedestal that the ssd sits on top of to allow space for the adapter card to fit underneath the m.2 ssd.

Everything works perfectly and temps are in the low 40's. Having 6.5 TB is more than enough for my large file
storage needs...and all incorporated into a single notebook unit. This is great. Also the weight reduction from
not having any HDD installed is great. I no longer have to worry about bumps and jarring due to moving around
with my laptop on top of my lap while wheeling around. The results are fantastic. Although I need to find a simple
way to secure the adapter cards a bit more.

Using black electrical tape would be okay from a safety standpoint (static electricity) but the tape tends to get soft
when warm and the adhesive gets stuck on everything...this is something I'd like to avoid. Although all 3 adapter
cards are secure and the m.2 ssd is secure as well, I'd be a tad bit more secure if the cards and m.2 ssd were in
place more securely. I've solved this issue by using black acoustic foam with sticky tape backside. This tape is
highly heat resistant and static charge resistant as well. I placed this foam inside the bottom of each bay to
provide cushioning, prevent static charge buildup, reduce heat protection, and to take up the open space underneath the adapter
cards.

I've also used the foam in places where the m.2 ssd and the dual adapter card come in contact...increased temps
have not been an issue since the m.2 ssd and the adapter card only come in contact in places where both cards
are just bare PCB.

Thank you for the link to the post joshindaphils. I found the posting quite helpful.