Gateway NV52 Laptop :: Black Screen & Power Issue!

I am using a Gateway NV52. Specs are at bottom.

Problem:

* Blank / Black Screen on startup
* Laptop sudden power loss at BIOS, DOS, MemTest86+ check

Details:

The laptop is able to power on and boot into Windows Vista fine. Infrequently after system sleep, shutdown, or hibernate then powering on after a few hours the blue LED lights up and a fan can be heard spinning but the screen remains blank / black. There are no red LEDs indicating the NUM Lock is on, HDD is loading, or the WIFI is active (normally these red leds are on as soon as the laptop is powered on). This tells me the issue isnt a bad LCD connection and such since the system would still boot into Windows (red HDD light).

The other issue, sudden power loss, only occurs outside Windows (BIOS, DOS). I performed a MemTest86+ (v3.4) in DOS. The check ran fine for a few minutes then the system would shut off. Running the test several more times produced the same problem but at different test areas. The shut off would occur from 1 min to 10mins. I have reseated the sticks but the same problem occurs.

I decided to go into BIOS Setup and let the system sit there. Do nothing but wait. After a few secs / mins it would shut off. I also hit PAUSE at the POST screen and allowed it to wait; again the system shut off after XX minutes. In both cases I've also tried tapping the CTRL key over and over in case there was some bkg timer but still the shutdown.

Within the BIOS there are no settings for system shutdown / sleeping / adjusting memory speeds. Very basic. For the memory sticks i pulled them out of the laptop and installed them into my other laptop and performed the same MemTest86+ check. The memory sticks were 100% fine. No errors. I also removed the battery from the laptop but ONLY used the AC Power, still the shutdown. I only used the BATTERY and still the shutdown.

** The sudden shutdown ONLY occurs outside Windows (within DOS, BIOS). Within Windows everything is fine. At the moment the sudden shutdown is not occurring, all is fine.

** Both issues occur infrequently.

There sounds like a serious hardware issue related to POWER. I am confident this has nothing to do with software. THERE IS NO WARRANTY ON THIS LAPTOP. I am willing to open this thing up and tinker around pending any suggestions. And for what it's worth i am using the latest Windows Vista 32-bit drivers (including Atheros WIFI) from Gateway's site.

It should be noted that about a month ago we replaced the laptop keyboard. Perhaps something could have been loosened?

System Specs:

Gateway NV52 Laptop
OS: Windows Vista Business
AMD Athlon 64 X2 QL-64 (Griffin)
Frequency: 2.1GHZ
System bus: 3600
Memory Sticks: 2 x DDR2 (2GB 2Rx8 PC2-5300s 555-12-E3 333MHZ) = 4GB total
Bus Speed: 200mhz
Mobo: Gateway SJV50PU
Chipset: AMD 780G
Phoenix Bios v1.03 (date: March 24, 2009)
ATI Radeon HD 3200 (RS780M) w/ 256MB (shared?)