my tinkering with this board so far
I bought my A8N32-SLI this past Saturday. I wanted something that would provide me with a more stable environment for CPU overclocks. My "trusty" SLI-DR has done me well, but it has never allowed me for the typical spectacular CPU overclocks that you see frequently see on this forum. (The reality of the situation, however, is that I have a few couple of good CPUs that need motherboards, so it's time to build a new 2nd box)
So without further adieu, I give you my random waxings on this new board:
Physically, the board is nicely laid out. It runs a LOT cooler then my SLI-DR when overclocking, so I think Asus is onto something with the 8-phase regulation. Major drag: the CMOS clear jumper is in a horrible spot if you are using a SLI video card configuration (or opt to put your video card in the bottom-most x16 slot, like I have); if you want to clear the CMOS, you'll have to remove the video card first.
I use a Big Typhoon heatsink. You can remove the top CPU bracket, screw in a couple of 6x32 2" screws right into the undermount and mount the BT like a waterblock. There is ample room around the socket, so if you are using a XP-120/90 heatsink, it shouldn't cause you to make contact with other mobo components (as was the case with the DFI SLI-DR). The fly-in-the-ointment, however, is that the ZIF socket makes for a tight fit with the Typhoon... the bottom of the Typhoon *just* misses touching the top of the ZIF socket. I'm assuming that I've mounted my heatsink reasonably well, but the CPU temperatures register 3-4 degrees higher on the A8N32 vs. my SLI-DR.
Compared to the DFI NF4 boards, this board has lot of arcane BIOS options unrelated to memory tweaking. The SB-to-NB, K8-to-NB settings are all uncharted territory for me, at least. I have no idea what the hell PEG Link is or what it does. (After reading the BIOS manual, I wonder if Asus does too)
I think the options for memory tweaking are on-par with the DFI SLI-DR/Ultra (but not necessarily the NF4 Expert board). Pretty much everything is there except (from what I could tell), the Twtr DDR setting. Also the Data Driving Strength is encoded differently (Disabled, 15% weaker, 30% weaker, 45% weaker) then on the DFI boards (Level 1, 2, or 3) so I'm not sure how to interpret the settings. You also have the option of turning off ECC support, which the DFI's do not give you an option for.
I am finding that I am getting better CPU overclocks with same voltage vs. the SLI-DR, although I am struggling with DDR timings. I can't tell if this is because of overvolting vcore (as some motherboards are known to do) or if it's just more stable vcore regulation.
I could easily run 4x512MB TCCD CAS 2.5 (@2T) up to 260HTT on my SLI-DR, however I cannot run these timings on the A8N32 stable except at/around 200HTT. (I had to run CAS3 for anything above 218HTT, which is killing my memory bandwidth) One thing I have noticed is that if you want to overclock to the same extreme levels of the DFI NF4 boards, unlike the DFI's, you cannot reliably use the Auto settings for some DDR timings, you really must explicitly set each value manually. (I'm using OCZ Plat 3200rev2 TCCD sticks, so your results may vary) Being able to set Vdimm in steps of 0.5v is a nice feature.
The only difference I have been able to tell between the (official) 0703 and (beta) 0805 BIOS is tha the K8-to-NB frequency now is specified as a multiplier option (1X, 2X, 2.5X, 3X, etc. in 0805 bios) vs. absolute frequency (1000mhz, 800mhz, etc in 0703 bios).
Tweaking this board requires "old-skool" overclocking methods -- aka DEL-BIOS-CHANGE-F10-REBOOT-TEST-REPEAT.AD.INFINITUM. Using A64 Tweaker to change memory dividers from inside Windows will lock the system. The CGNV4F utility (or whatever it's called) to change HTT etc on the fly doesn't work either, it won't even read the current settings. The Asus-supplied AIBooster overclocking software is absolute poo, so don't bother installing it. (Any changes in overclocking changes in AIBooster force a reboot... why bother?) Memtest86+ V1.65 doesn't recognize the fact that this is a NF4 chipset board, but works otherwise.
Interesting tidbit: I set my vcore to be 1.5v by enabling the "Overvolt CPU Vcore" option (adds +0.2v) and setting my vcore to 1.3v. Using Asus Probe II (Electric Boogaloo) the vcore is reported as 1.5v, but it's reported in CPU-Z as being 1.3v! Your guess is as good as mine why that is!
I expect that a few days of tweaking will let me sort things out here, but at the moment it looks promising, but it is not all roses yet. A large, large, large segment of the overclocking community employ the DFI SLI/Ultra boards so the A8N32 is currently at a disadvantage here... it will take some time to fully understand this board and its quirks.
Hope this helps people who are deciding between this and the DFI SLI-DR Expert board.
