[SOLVED] GA-MA785GMT-UD2H v1.1 erratic behavior when coldboot

[crazycheese]

Hi, I have this problem right from start and I thought it is a memory issue.
The system does not work correctly when cold-booted(complete AC off for at least 20 mins) - windows will freeze at boot logo, linux will sometimes mention that some CPU cores are not responding, sometimes not - but once within desktop applications crash or drop with segmentation faults randomly.

However, when I power it off and power it on again per normal button (note reset does NOT help) - there are no problems anymore. Everything works, in both OSes. This was confirmed many many times - power off, power on and problems gone...

I have:
AMD Athlon II x4 630 processor BL-CL2 at stock speed, cooled with Scythe Big Shuriken@~40C on full load
2x2GB Excelram PC3-12800U (1600) - E3-416D99
400W psu, it has 20pin ATX (connected into 24 connector) and 4 pin which is connected into 4x2 connector
Voltages stay within ranges
HD4770, 6pin supplied via independent 5V
The case is very good vented.

Things that I tried and did not help:
- BIOS upgrades
- I have tried moving memory around
- going to 1333 SPD
- highering memory voltages
- running memtest, after second boot it works rock stable
- highering NB VID
- undervolting CPU to 1.2 v

I have no idea why it behaves so. Has anyone ever experienced something similar?

[absic]

Hi there,

looking through your system specs and from my own experiences I would suspect that you are slightly underpowered, especially as Gigabyte recommend a PSU of at least 500 Watts for this motherboard.

[crazycheese]

Hi, thanks for reply!

The motherboard + CPU + gfx at full load consume no more than 200W.
If I undervolt the ridiculously high stock vcore (which is absolutely ok with propus, confirmed from AMD techie), the CPU goes down from 140W to ~ 110W, resulting in even lesser load.
I could measure around 80W consumption in idle state and 140-160W when compiling, gaming, 194W was with both furmark and sp go2004.


BUT
I think you may very well be right. Esp when on the start system demands just a bit more and if the power distribution is not optmized (delays etc) in that motherboard..

Also, I have 20pin ATX and only 4-1, this may mean that lots of power is spend on molex and mainboard itself, especially in power-on state just does not get enough juice provided. Maybe it is expected to get this provided, since 24pin are for long time on the market.

If I add capacitor volume reduction over the years, and mine PSU is ~3,4 years (but still somehow quality one from bequiet), it may be delivering only 80% of its original capacity.

I think I give you this binary cake for help! Thanks!

[absic]

Thanks for the cake!! 

Yes, Power Supplies do fade with use and time and I would definitely but looking at the PSU, if only to eliminate it as the cause of your woes.

Good luck and let us know how you get on.

[Dark Mantis]

Hey nice bit of cake there absic...any chance of sharing?

[absic]

Sorry DM, the wife scoffed the lot! 

For a tiny Japanese lady she can really tuck her food (and mine) away!