Hello everyone, I have a northbridge overheating problem (probably) with my pc. I'll start from scratch. I'm not overclocking anything. Used this build with Asus MB for about 5 years without a problem. Build is following: Motherboard: Asus M4A785TD-M EVO / MSI 970A G43 CPU: AMD Phenom II X4 945 3,00GHz (95W version) Graphics: XFX Radeon HD 5770 (HD-577A-ZHFC) RAM: A-Data XPG Gaming Series DDR3 1333MHz 4GB (2 x 2GB) AX3U1333GB2G8-AG currently at 1,5V with 9-9-9-24 timings (sticker on modules says 1,65-1,85V, 8-8-8-24) HDD: WD Caviar Black 750GB (WDC WD7501AALS-00E8B0, 7200RPM, 32MB Cache, SATA 3.0Gb/s 3.5") PSU: FSP Group Blue Storm Bronze 500W Operating System: Windows 7 Ultimate 64bit Antivirus: Eset Smart Security (using it since I got this pc) I'll be talking now what is happening when I use the Asus motherboard. So in the last two months my pc is freezing and randomly shutting down. Freezes act as following: they are pretty random, but they mostly happen when I run something that needs resources e.g. watching stream, playing games, but sometimes also when pc is idle on desktop. At start of the freezes, whole pc (including sound, screen, mouse) freezes in like 1 second intervals (1sec frozen, 0,5sec normal) and as time increases they go faster e.g. 0,5s; 0,25s till the pc freezes completely (I can easily replicate those freezes for example while playing CS:GO), in that point I have to hold power button to turn pc off, or press reset. If I boot again after this happens, almost everytime the pc will freeze or shutdown in like 2minutes. And about the shutdowns, in fact they do happen "instead" of freezing. Also very randomly. Simply when the NB temps (probably) get too high, pc shutdowns. Sometimes it's a BSOD (got some dumps, mostly 0x124 stops, but some others too, uploaded with post). When this happens I have to turn off pc the same way as with freezing. Pc hangs "before" bios, doesn't boot or anything. Screen is black as well (no signal sent). Now about what I think the problem is. At first I started to watch temps using HW Monitor, all temps were and currently are in normal limits, CPU doesn't go above 60°C, GPU max around 65°C, two motherboard readings, 1st max 55°C, 2nd max 45-50°C, HDD max 42°C. But all the time the temps were fine, so when my pc froze/shutdown, I tried to touch CPU and GPU heatsinks which are warm. BUT heatsink of NorthBridge chipset and RAM's (they got heatsinks) are very hot, everytime I do this, I can't hold my fingers on it for more than 3 seconds. The NB heatsink tends to be even hotter than RAM. I already replaced thermal paste (I'm using Arctic MX-2, replaced on CPU and GPU as well) on NB heatsink, the old one was already dried out, so I tough it will help, but nothing changed. And now about the MSI motherboard, because everything suggests that this is a hardware problem, I ordered a new MB (decided trying out MB now, because before problems described above, I also experienced big number of random shutdowns and bluescreens, mostly 0x124 again and also sometimes bios was telling me that new CPU got inserted, which obviously wasn't), I got it yesterday, so I uninstalled drivers of the Asus MB and some other things, that have to do something with Asus. I replaced the MB, setup up bios, installed MSI drivers and stuff and after like 3rd or 4th reboot, pc started crashing again (no freezes yet, this mb probably acts differently, will update if I get any). I did not even managed to play any game as the shutdowns happen so fast, they happen on desktop or in browser. But the main thing is that heatsink of NB chipset is hot as hell again when pc crashes, here I can keep finger on it like max 1 second. MB readings from HW Monitor are fine. I'm writing this with case's side panel off and desk fan blowing on it (I have the panel taken off for about those 2 months of problems). List of things I tried to solve this: Updating Windows and BIOS(I had latest version of BIOS even before problems), GPU and chipset drivers, reseating all components and cables (like 5 or more times, sometime it helped for like 1 day, then problems got back again), changing MB battery, stress testing CPU(Prime95) and GPU(Furmark) no crashes during both, ran tests like CHKDSK (no bad sectors), SFC (nothing repaired), MDSCHED (windows memory test, passed), memtest86 (like 3 or 4 times with 9 and more passes in last 6 months), running quick and extended tests using WD's HDD diagnostic program (checking HDD's SMART info, everything is ok except UltraDMA CRC Error Count which value is at 3, did not rise in last week, I don't know if it was there before, none of the programs I checked SMART with, didn't show any problem like red cross at this error, health status is good or ok in some programs), changing PSU's (I measured both with digital multimeter, all values are in the 5/10% ranges, I can post them if needed), running pc with just one RAM stick (switched them many times, dimm slots they were in also, also tried diffent slots with both sticks) and last but not least clean install of Windows. I really appreciate any comments that could help. I am sorry for my terrible English. Thanks for helping and reading.