Homebuild issues, switches on then off

[dollidarko]

Okay guys, I've read similar threads on here about this but nothing quite the same... sorry for the book, please bear with me here ^^;;

Back story: bought a build from Craigslist (i know, i know) a couple years back. kid botched something and tried to play it off as him just selling it for bills, brought it home, issues, turned out that it was something silly, fixed it, ran smoothly after that.

FF to a few weeks ago. Hear a loud crack like a CD snapping while i was laying down waiting for a game to patch. shut down, next day disassemble and nothing seemed popped so i wrote it off as something falling. Nothing was amiss. FF again to last week. Computer was acting wonky (mobo screen would hang, usually went away after a couple restarts) so i took a day off to clean her out. unplug from wall, etc... plug everything back in and everything would switch on, but would not post. Breadboard it, try again... same thing. Take everything out and super clean it, realize the kid used a 530w psu. remember the crack noise, open it up... blown capacitor. oh boy. let it sit for a couple more days until i had the cash to get another psu.

buy an 850w thermaltake smart series m psu at my local best buy and put it in that night. hit the power button, lights and fans will come on for a split second then shut off. let go of the button, same thing. take the mobo out of the case and put it on my wood table over cardboard, clear cmos, tried turning it on with nothing but the freshly reseated cpu and heatsink/fan, cpu and mb power cables were indeed plugged in. same thing happened. got ticked, hit the button consecutively, eventually came to life and beeped at me for ram. put a stick of ram in, took longer to go on but it did, got the gpu beeps. put that in, powered it, wouldn't go. joy.

Now, i know there's a list of compatible power supplies for amd processors, and the psu i grabbed wasnt on it. but the power supply that was in there originally wasnt on the list either, and aside from it being underpowered, it worked fine. so, my question is... what the heck do i do now?

specs:

870-g45 motherboard
2x 4gb ripjaw ram
radeon hd6850 gpu
phenom II x3 cpu (though the mb screen says x4)

I'm currently at work, so if I missed anything, I apologise. Thank you in advance!

 

[nathanoakes]

Not really an expert on the whole PSU compatibility list, but I think it's total balls. If you're using a PSU that has a switch on the back for 230v/160somethingv, make sure it's on the right setting. I think the crack was an electrical pop from the power supply, much like I had a few weeks ago and it may have fried your motherboard. If you can get hold of a friend's computer, ideally one with the same socket type as yours, you should try your parts in their motherboard to make sure they all work. My opinion is it is a fried board so maybe try to buy one, then when it comes you can put the old one in the box and pass it off as faulty Your BIOS says you have a quad CPU because you do. AMD do a nice little trick where they have 'faulty' CPUs that don't pass on all of their cores, for example, a quad core with one core that didn't pass the manufacturing tests. They then disable that core and pass it off as a tri-core chip which can be unlocked by supporting motherboards. You're one of the lucky ones!

 

[dollidarko]

Yea, I figured holding off until the build was completely stable (and tricked out) before I messed with the core unlocking feature.. and i assumed the pop was indeed the psu, thus why I mentioned it in the long winded tale of frustration

The psu that was previously in was a "switching" power supply, which I figured had something to do with the active phase switching feature of the motherboard... which might explain why the thermaltake didn't cooperate. It didn't have the switch on the back either, i do remembering checking for that.

My next course of action was going to be buying a "switching" psu that is on the approved list, just to cover both bases. But I'm a bit wary, so I would ask about my woes first instead of dropping $150 and twiddling my thumbs for a few days in wait.

 

[nathanoakes]

Yeah I just got a nice 8 core processor, very happy indeed I'm a bit of an idiot with electricity to the point where I don't care about any damage to myself, so I plug things into the mobo with the computer on, meaning I'm pretty used to these pops. Anyway, I have a switching PSU and put it on the wrong setting before, which did actually fry the board so it's a pretty strong issue. Lucky I had a backup. Try getting hold of a cheap board first, there's an ASROCK one that will fit your CPU in for £40 so maybe like $70? Not too sure on the conversion rate. It's most likely your issue in all honesty

 

[dollidarko]

How do you think I would test that, though? As I already need a new psu, I don't really have the money to drop on another mobo if that isnt the issue... as childish as it sounds, it beeping at me was like a sign of life to me.

 

[nathanoakes]

Well like I said the only real way to test a bad board would be to use a different one. Do you know anyone who has an AM3 motherboard? I can't think of it being anything else, but it could be a few things like two burnt out RAM sticks or RAM bus errors. You could try a different PSU but I highly doubt that's the problem. You can buy a really cheap PSU tester on eBay and check that everything reads fine but otherwise just get hold of a different board. Sorry :/

 

[dollidarko]

Ah, the only friend I have with an AM3 motherboard is in Ohio (I'm in NJ)... otherwise they're pretty computer illiterate. I'll order the other psu at some point in the next few days, if it's still acting wonky I'll try another board... the 870-g45 is discontinued, though, and I doubt MSI will be willing to lend a hand...

 

[nathanoakes]

Honestly you're probably better off getting the motherboard first off. If it isn't the problem just return it saying it doesn't work and then get the PSU. Like I said there's a cheap ASROCK board on eBay, I can get the link if you like?

 

[dollidarko]

I don't currently have a working psu is the thing, i returned the thermaltake to bestbuy the other day. The one I had pretty much died :/

 

[nathanoakes]

Oh unfortunate :/ I can recommend a set of cheap parts for you if you can tell me the budget?

 

[dollidarko]

Update: Ordered a new psu and motherboard from newegg that i installed this morning, I'm not sure if it was the psu or the mobo but its working just fine. Thanks for the help

 

[nathanoakes]

Ah good, anytime