Mac Pro 5, 1- PCIe Configuration

Question

Level 1

17 points

Mac Pro 5, 1- PCIe Configuration

Hello,

I have upgraded my Mac Pro 5, 1 (mid-2010 model) with some PCIe changes/additions and need some advice. Quite frankly, I was surprised by the fact that the Expansion Slot Utility was not usable here and the older interface to help me tweak the best configuration. Reading on the possible configuration options is starting to sound contradictory between reseources. Regardless, here is what I have:

Slot 1 (16x)- ATI Radeon 5770 graphics card

Slot 2 (16x)-ATI Radeon 5770 graphics card

Slot 3 (4x)- empty (no physical space due to above)

Slot 4 (4x)- Sonnet PCI Tempo SSD Pro Plus card

So, does this configuration look effecient for the priority of data read/write performance verses graphics performance?

Peace,

Dr. Z.

Mac Pro, OS X El Capitan (10.11.6)

Posted on Aug 31, 2016 7:11 PM

Reply

Answer 1

Best reply

Grant Bennet-Alder

Level 10

126,937 points

Sep 1, 2016 7:34 PM in response to zeigh

The PCI slot utility is not usable on the 2009 through 2012 Mac pro.

The allocation of slot-speeds on the 2009 through 2012 Mac Pro is fixed, not configurable, and is exactly as you state: the two lowest slots are 16x slots, the two upper slots are 4x speed, but "provide support for up to 16x cards" (in other words, they use the largest connectors, but everything beyond 4x is not connected).

Your setup looks just fine. Some users prefer to leave the top slot open for better air movement above all the cards. But as you said, you don't have that option.

4x is plenty fast enough for that SSD card. That is pretty much as fast as they are making those cards at this writing. Additional speed such as a 16x slot could not possibly be used at this writing.

Reply

Answer 2

Sep 1, 2016 7:35 PM in response to zeigh

That particular SSD card is only able to use 4x PCIe lanes so putting it in a 16x lane slot would make no difference at all.

In fact all but one SSD card adapters are 4x because a single SSD drive even the fastest is about 1500MBps and this is possible to do with just 4x lanes. The one card which is different is a 16x lane adapter made by Amfeltec call the Squid. It uses the extra lanes/speed to drive up to four standard SSD cards in a software RAID setup giving you therefore in theory 4 x 1500MBps of speed.

See http://barefeats.com/hard210.html

Reply