P5E3 Premium PCIex16 slots, up to the job or not

[Jim]

Hi group, I have a basic question regarding Asus P5E3 Premium, it comes
with 3 PCIex16 slots, 2 run at x16 speed (X48 chip-set) and the Black
one runs at a max of x4, I want to run a Asus EAH6450 passive video card
in one x16 slot, then I need to run both a USB3 card (not bought yet)
and a Adaptec 1430SA
http://www.adaptec.com/en-us/support/sata/sataii/aar-1430sa/ this will
only be used for non raid work, just gives me 4 extra hard drives in the
system for storage, now where would it be best to put the USB3 and
Adaptec cards, I know the Adaptec will run in x4 but that is the min,
but no idea what a USB3 card will need, your advice is welcome.

TIA

[Paul]

I think the answer is both simple, and complicated. Simple in that,
if you ignore the details, you can just plug the cards in, and all
will appear to work. You could stop reading right here, and not
see any problems, no matter what you do.

*******

First, let's start with USB3. It can do 336MB/sec using the fastest
available USB mass storage driver for it (theoretical number). A PCI
Express x1 Rev.1 lane runs at 250MB/sec. A PCI Express x1 Rev.2 lane runs
at 500MB/sec. It looks to me, like to achieve the theoretical max, you
want a revision 2 lane. Note that to date, USB3 external disk enclosures
peak at around 200MB/sec, and there is only one USB3 peripheral which
feels "pinched" by this limit. 99% of the available toys, will be
perfectly happy, even if the USB3 chip is on a Rev.1 lane. (That's
part of the "don't worry, be happy" approach in the first paragraph.)

The cards I see for sale today, for USB3, are x1 Rev.2 . They will run in
a Rev.1 slot no problem. But if run in the Rev.1 slot, the transfer rate
will be limited to the 250MB/sec lane limit. An alternative way to build
the cards, is to use PCI Express x4 Rev.1 switch chip to x1 Rev.2 on the
plug-in card, which was done by Asus on the U3S6 card. I don't see a card
following the design idea of Asus, offered for sale now. So it looks like
price overrules functionality. The U3S6 card wasn't fault free, and you'd have
to check the reviews to see how much "hair pulling" was involved to
get the card completely 100% operational. So this is an example of a card
using x4 Rev.1 lanes, to build Rev.2 lanes for internal usage. It
gives you better USB performance, assuming the motherboard has an
available x4 or bigger slot.

http://www.newegg.com/Product/Product.aspx?Item=N82E16813995004

OK, so you have the two x16 slots, and they're Rev.2 . If you stick a
typical $25 USB3 card in the second x16 blue slot, the theory is, it will run
at Rev.2 rates. Rev.2 uses a low jitter clock, which is part of the requirement
to get it to work. And I guess the Northbridge X48 has the necessary clocks
to the two x16 Rev.2 slots it supports.

The Southbridge is likely to support six x1 Rev.1 slots. Using a Tomshardware
review, I was able to correct my first impressions. It doesn't look
like there was any game playing here. The third x16 slot gets an honest
x4 Rev.1 interface, as near as I can tell.

In the P5E3_Premium_v2_manual.pdf, I see

JMB363 x1 Rev.1 PATA,SATA storage
88E8056 x1 Rev.1 LAN (GbE full performance)
RTL8110SC PCI 32 bit LAN (GbE)
FW3227 PCI 32 bit Firewire

(x4 left) x4 Rev.1 Real x4 wiring (in physical x16 slot)

If you connect the Adaptec 1430SA to the third slot, you'd have a
peak bandwidth in the slot of 4x250MB/sec, which should be plenty
for individual disk drives. Also remember, that the Southbridge PCI
Express lanes, pull bandwidth through the hub bus, so there is all
sorts of sharing going on there. I don't think that's an issue,
merely pointing out that you have to do a complete analysis if you
wanted to see every detail.

LGA775
|
2*x16 Rev.2 ---- X48 --- DDR3 dual channel
|
| Hub bus (named DMI?)
|
ICH9R --- SATA, PCI, whatever else
|
| six x1 Rev.1 lanes
|
2 chips plus x4 slot

So plug your 1430SA into the last slot, plug the USB3 into the middle
slot. If you can really detect some issue with the 1430SA, and
don't care about a 250MB/sec limit on the USB3, you can swap slots.
If the USB3 is put in the third slot, it's peak is less than 250MB/sec.

The only device that cares about "true full rate USB3", is the
Intensity Shuttle. Or perhaps, any clones or copies of this thing
(there are other designs similar to this now). Notice that the advert
here, refers to an "X58 motherboard", which is a vague reference to
running the USB3 chip off a Rev.2 port, as far as I can detect. The
software for this product, actually had a bandwidth test, so it could
warn you that your hardware was inadequate -- after you'd bought the product.

http://www.amazon.com/Blackmagic-Design-Intensity-Computers-Professional/dp/B003WSQTWU/ref=sr_1_1?ie=UTF8&qid=1324028873&sr=8-1

HTH,
Paul

[Jim]

Hi Paul, firstly sorry for the delay in getting back to you but what
with crimbo and all things got way laid.
WOW Paul some answer to what I "thought" would be a simple"ish" question
I had to read your post a few times to get my head to understand it
which i do now, I already have the 1430A card here and bought a 2nd user
U3S6 card from ebay the other day (still waiting for royal mail to del
it though), I'm going to do as you suggest and put the 1430A in the last
slot and and run some tests and see how it goes.
Once again sorry for the delay in getting back to you and many thx for
your help here.

Jim