Asus M5A99X EVO R2.0 and PCIe x16 slot issues

Ahto Taat

Reputable
Jun 24, 2014
1
0
4,510
Hello.

Ran into weird issue with this motherboard. I wanted to use LSI MegaRaid hardware raid controller card in my machine. Initial setup looked like this

■First PCIe x16 slot - graphichs card (Nvidia Geforce GTX 660)
■Second PCIe x16 slot - RAID controller card
■Third PCIe x16 slot - empty

After booting up, I noticed that Win7 Aero desktop is feeling sort of sluggish and laggy while moving mouse cursor around the desktop. Reinstalled drivers couple of times, changed their version backward and forward - no change. Finally downloaded GPU-Z and noticed that it showing x1 (!) mode for graphics card.

After removing the Raid controller from motherboard, GPU-Z reported graphics card working in full x16 speed mode. Resubmitted raid controller into second PCIe x16 slot again, just to be sure and desktop became laggy again. Bunch of reboots/shutdowns in-between of course.

Finally, I found out that I could use raid controller in the 3rd PCIe x16 slot without it killing off graphics performance. Problem is, it's x16 size slot but working in x4 mode. That particular raid controller works normally in x8 mode (x8 PCI Express 2.0), so half the performance is theoretically lost.
Which becomes problem once I become upgrading my system to use SSD's in RAID0. More than couple of SSD's in RAID0 would saturate PCIe x4 available bandwith (planning to use Sandisk Extreme II's).

Final working setup looked like this
■First PCIe x16 slot - Graphics card
■Second x16 slot - empty
■Third x16 slot - RAID card

I'm interested if anyone has ran into similar issues with the PCIe slots using this motherboard, either using some other cards (perhaps PCIe SSD's or NIC's) or raid controller. And if they found any solutions better than using 3rd and slowest performing x16 slot.

I tried using graphics card in second x16 slot and raid in the first. Can't recall exactly what the result was but it did not work out.
 
Solution
I remember working with this board. Not a winner imop. I liked how they claimed quad sli/xfire support but only have 3 pcie x16 slots, one of which couldnt even run in x8. Lmao.

Anyways, putting anything in the pcie2x16_2 slot will drop the _1 slot to x8 mode... odd considering AMD cpu's have 40 pcie lanes

popatim

Titan
Moderator
I remember working with this board. Not a winner imop. I liked how they claimed quad sli/xfire support but only have 3 pcie x16 slots, one of which couldnt even run in x8. Lmao.

Anyways, putting anything in the pcie2x16_2 slot will drop the _1 slot to x8 mode... odd considering AMD cpu's have 40 pcie lanes
 
Solution
Mar 7, 2015
2
0
4,510
Your existing configuration ( last ) is best. The black x16 slot is running at x4 speed. When you removed the raid card from the second x16, the first x16 went back up to full x16 rather than the x8 it goes into when another board occupies the second slot. This is typical for sli/crossfire configurations ( but sub par for a board feature ).

You may try moving you video card into the black slot and see what kind of graphics hit you take running it at x4 If you really need to emphasize raid performance.