At the request of forum members, here is a thread to further discuss the A8R mobo from Asus. this is now broken from the original thread over here which dealt with the *32 model as well. A quick recap from my colleague Stuart "Veridian3" Davidson and his talks with asus regarding the problems with this board. ___________________________________________ OK guys, Asus have responded to our email which contained all your feedback on the A8R-MVP. Here is the unedited mail, please let us know any comments you would like fed back to Asus re the response and any further questions it raises. Issue 1 A fix is needed for the fluctuating vcore. ie: when set in bios @ 1.45v + auto overvoltage it reads (fluctuates) from 1.488 > 1.536v. A simple fix may be just to add an option of .2v overvoltage or open more options in bios. ie: 3200 venice default voltage 1.4v maximum option in bios 1.65v. Or Big voltage fluctuation on vcore (sometimes it can go from 1.37v to 1.44v (readings made with Asus Probe). Or AMD 4200+ allow max of 1.48v (1.4v +overvolt) however fluctuates down as far as 1.41v Asus Response The Vcore will not be contantly fixed at a voltage point even if the CPU loading is kept. Additionally, switching noise and any high frequency operations of CPU also make Vcore variant. The reading from hardware, temperatures & voltages are translated from analog to digital converter (ADC) in hardware monitor chip. It will not be 100% accurate. In addition, the hardware monitor in a PC system also has a certain range of variation. Besides, the power for hardware monitor will also varies and impatcs the reading. Voltage fluctuation is inevitable. Therefore, if the variation is within 50mV, we can consider it stable. Issue 2 The A8R-MVP is advertised to reach up to 1.65V on the Vcore. Depending on the processor installed, the max you can actually select is either 1.40V or 1.45V (The Opteron 148 allows selections up to 1.45V). The "Vcore Overvlotage" option is supposed to give up to .2V OVER whatever you manually select. If you select 1.45V and "Vcore Overvoltage" on, the processor should be able to get up to 1.65V. However the Vcore will not go over 1.55V no matter what, and fluctuates quite a bit! Asus Response We are following AMD's specification. VID+50 is what AMD defines and Asus increases it to 100. This +100 limit is to protect user's CPU. A8R-MVP is designed for the mainstream market so we take more conservative options for it. CPU type --- Recommended Voltage --- Maximum VID adjustable --- Maximum Voltage after Vcore over-voltage Enabled(+0.1V) Clawhammer 1.50V 1.55V 1.65V Opteron 1.40V 1.45V 1.55V Some new 90nm CPU 1.35V 1.40V 1.50V According to AMD Cool&Quiet spec, VID's overvoltage limit is 50mV (2 steps), together with the additional 0.1V. The maximum voltage setting should be default Vcore voltage + 50mV +100mV= default Vcore voltage +0.15V. The mentioned max 1.65V is possible only on some Athlon 64 Socket 939 CPUs which the highest voltage is about 1.50V. This doesn't mean that A8R-MVP supports 1.65V on every CPU model. For example, enthusiasts like to use Opteron 14X/15X CPU which has a default VID 1.40V. Thus the max Vcore can be set to be 1.40+0.15=1.55V. Issue 3 Vcore reads higher than what it's set at in BIOS and in Asus Probe (I don't have a DMM). For instance, 1.35v shows at near 1.40v (or even higher because of fluctuation). Asus Response When CPU is idle, the Vcore voltage reading usually looks a little higher. If the loading gets heavier when running program, the Vcore voltage shall drop down a little. That's a normal phenomenon in a regulator design. Issue 4 Some users reporting that they are unable to use 1T even at stock speeds. (Results in random reboots and errors). There are many postings here which cover this issue: http://www.ocworkbench.com/ocwb/ultimatebb.php?/topic/44/91.html http://vip.asus.com/forum/bbs.aspx?SLanguage=en-us&model=A8R-MVP Asus Response According to AMD's spec, 2T is the suggested value. Not every memory module on the market could perform or operate well under 1T so this really depends on the loading of memory module and quality of memory chip. In our previous experience, only light loading DIMM like 1 single side with top-grade memory chip can be easily set to 1T & work well. If a double side DIMM is used, or with B/C class chip, or with more than 1 DIMM on each channel, 1T is more difficult to achieve.