Sometimes no POST - cannot ID the problem

flashfir

Distinguished
Nov 24, 2010
196
0
18,710
I'm describing a problem that isn't crippling but seriously annoying. I'm thinking its the motherboard since I've run MEMTEST+86 overnight for 9 passes and my RAM showed up fine.

Sometimes my computer does not POST. Sometimes it does when I don't do anything. Sometimes it does after I use the hard-reset button. Sometimes it doesn't and I have to pull RAM in and out, permutations have been tried, sometimes resetting the CMOS eventually it boots up.

Once I'm in Windows, I'm golden. That's why I'm keeping my rig on for most 24/7 now since I don't want to take the chance of opening up the case and touching the RAM and turning it sideways, righting it side up turn on, off, sideways, repeat...

It's not the RAM slots because I have 4. It's failed to POST using my individual sticks in either BLUE or BLACK pair. It has also failed to post obviously with both of them in the BLUE or BLACK.

What should I do?
Thanks in advance. :D

---
RIG SPECS:

G.SKILL Ripjaws Series 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model F3-12800CL9D-4GBRL
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231277

ASUS M4A77TD AM3 AMD 770 ATX AMD Motherboard
http://www.newegg.com/Product/Product.aspx?Item=N82E16813131603


AMD Phenom II X4 955 Black Edition Deneb 3.2GHz 4 x 512KB L2 Cache 6MB L3 Cache Socket AM3 125W Quad-Core Processor HDZ955FBGMBOX
http://www.newegg.com/Product/Product.aspx?Item=N82E16819103808&cm_re=955-_-19-103-808-_-Product

CoolerMaster Elite 430
http://www.newegg.com/Product/Product.aspx?Item=N82E16811119227

OCZ StealthXstream II OCZ600SXS2 600W ATX12V v2.2/ EPS12V 80 PLUS Certified Power Supply
http://www.newegg.com/Product/Product.aspx?Item=17-341-039&SortField=0&SummaryType=0&Pagesize=10&PurchaseMark=&SelectedRating=-1&VideoOnlyMark=False&VendorMark=&IsFeedbackTab=true&Keywords=(keywords)&Page=1#scrollFullInfo

SAMSUNG Spinpoint F4 HD322GJ/U 320GB 7200 RPM 16MB Cache SATA 3.0Gb/s 3.5" Internal Hard Drive -Bare Drive
http://www.newegg.com/Product/Product.aspx?Item=22-152-244&SortField=0&SummaryType=0&Pagesize=10&PurchaseMark=&SelectedRating=-1&VideoOnlyMark=False&VendorMark=&IsFeedbackTab=true&Keywords=(keywords)&Page=1#scrollFullInfo



HIS H585FN1GD Radeon HD 5850 (Cypress Pro) 1GB 256-bit GDDR5 PCI Express 2.1 x16 HDCP Ready CrossFireX Support Video Card w/ Eyefinity
http://www.newegg.com/Product/Product.aspx?Item=14-161-330&SortField=0&SummaryType=0&Pagesize=25&PurchaseMark=&SelectedRating=-1&VideoOnlyMark=False&VendorMark=&IsFeedbackTab=true&Keywords=%28keywords%29&Page=1#scrollFullInfo
 
No POST as in everything appears/seems to be working, but no display? If that is indeed the issue, I would run some tests on your GPU and PSU, just to make sure.

GPU Tests:
1. Power on your system. Let it POST or attempt to. Succeed or fail, turn off the system. Do this 5 times. Jot down how many of the 5 times resulted in "No signal" on your monitor.
2. Swap out the GPU, then repeat step 1.

PSU test:
Use a digital multimeter to check the voltages on the P1 connector.

Red = +5V
Yellow = +12V
Blue = -12V
Orange = +3.3V
Brown = +3.3V
Green = +5V
Gray = should go from 0V to 5V when you turn on the power
 

flashfir

Distinguished
Nov 24, 2010
196
0
18,710


Just to clarify: When you say everything working it means all kinds of fans & HD spinning just no POST beep nor any output to monitor.

I don't have a digital multimeter :(
I'll do what you suggest for the GPU but I've kinda done that before since this episode has occurred so many times. And 90% of the time turning it on and off and on and off multiple times does not change anything.
 

flashfir

Distinguished
Nov 24, 2010
196
0
18,710
Spent 30 minutes this morning, learned something new.

What is the likelyhood that 2/4 of your RAM slots on your MOBO are broken? One in each of the Dual Channel pairings... I'm running 4gb on single channel now. DUMB.

badb.png


Both are supposed to go in black or both in blue. Right now I have one in the 2nd and 4th because the highlighted 1st and 3rd ones I cannot get it to boot single stick (tried with both my 2gb modules individually) NOR with both in BLUE or BLACK.
 

flashfir

Distinguished
Nov 24, 2010
196
0
18,710
I did in my testing. Can explain how that's different than the two further? I did and it took an extra 5 suspicious seconds to post beep, is there an explanation for that?

Just went into bios lowered my modest 3.6oc to 1.375vcore and now no post. Shoulda just kept the computer on! Rats
 

flashfir

Distinguished
Nov 24, 2010
196
0
18,710
Problem seems to have disappeared right now by putting my computer horizontal. *incredulous*

The POST beeps occurs quickly like NORMAL rather than like 5-10 seconds after I push the power button/reset.
I'm in the two slots closest to the processor.
 

flashfir

Distinguished
Nov 24, 2010
196
0
18,710
New update: I'm in the two black slots right now *see image above*

It always posts when I have the computer lying horizontal rather than vertical.
Elite+430+Black.jpg


Why would this change anything?
 
Maybe it's something to do with the case. Have you tried bread boarding? If not, do so, but also turn the mobo vertical to see if the problem still happens with the mobo outside of the case.
 

flashfir

Distinguished
Nov 24, 2010
196
0
18,710
Recently I got a memory manegement blue screen and I just ran memtest today and it failed multiple times most within the same test 3rd hour in today.

Is it possible that a mobo might cause good ram to fail memtest? If not then I know 100% my ram was slowly going bad and was the culprit these past few months!
 
AFAIK, the only ways (which are a stretch) for the mobo to cause the RAM to fail would be:

1. Over volting too high; and
2. A virus designed to attack the BIOS

In all likelihood, the RAM was always the problem. If MT86+ shows errors, replace the RAM. If the problem persists after new RAM, RMA the mobo.
 

flashfir

Distinguished
Nov 24, 2010
196
0
18,710


Errr I was asking if it was possible for the ram slots on the mobo to be defective in such a way that the ram put into it wouldn't function 100% ok.

Thanks for your help but right now I dint see a best answer selection button >:/

Rma ram is going in a few days!