Jean Delvare wrote: > On Mon, 08 Jun 2009 10:05:08 -0400, Frank Myhr wrote: >> Jean Delvare wrote: >>> You could contact the motherboard vendor and tell them about the >>> problem (the question is "Is VID5 properly routed from CPU to >>> IT8716F?") and see what they have to say about this. >>> >>> I don't really know how to work around this. I suspect that only the >>> late 0Fh family CPUs actually make use of VID5. If I am right then we >>> could tweak the hwmon-vid VRM selection table and use 5-pin VID (VRM >>> code 24) for some of the 0Fh family CPUs. I don't know where to put the >>> limit, and this is fixing the problem where it is not... which is >>> likely to cause even more problems on other systems in the future. >>> >>> Frank, can you please tell us for which 0Fh family CPU model you did >>> need the 6th VID pin decoding originally? >> Hi Jean and others, >> >> I'm sorry, that system is currently offline and I (not so) cleverly >> didn't back up log files so I don't have kernel-reported cpu info. But >> here is hardware spec: >> >> cpu: AMD Athlon X2 64 4850e, ADH4850IAA5DO >> mainboard: Gigabyte GA-MA770-DS3, IT8718 > > Mmm, this is strange. This CPU should operate at 1.1 to 1.25 V just > like Hleb's. For this range the 5-bit VID codes are sufficient (VRM > code 24 in hwmon-vid). Thus it shouldn't have made a difference when > you added support for 6-bit VID codes. Do you remember why you wrote > that patch in the first place? I dimly recall that it87 was reporting my cpu voltage incorrectly. In the course of investigating that I saw AMD 32559 Table 71 and decided to update hwmon-vid to match it. I think I continued to have sporadic problems with incorrect VID being reported after making the change. And in any case, I wasn't using voltages in the range that would have required 6-bit VID decoding (see below). > Actually I am not aware of _any_ 0Fh family CPU model running at a core > voltage below 0.9 V. This makes me wonder if we shouldn't simply map > the 0Fh family to 5-bit VID decoding and be done with it. This would > avoid potential issues such as the one Hleb is hitting (although I > don't disagree this appears to be a mainboard wiring issue in the first > place.) > > Opinions? I was undervolting the cpu, but still limited to 0.8V or above by BIOS. No objection here to go back to 5-bit VID decoding. Sorry for the problems my patch apparently created :-(
