OK. Yesterday had problems with flash in firefox. Had to close firefox process, because it hung up. After restart screen blinked during w7 loading - looked like someone unplugged and plugged monitor, but then everything was allright. I turned it off. Today i have a reset loop. When it's off the RED LED S4/5 lights.
S0 or C0
The system is turned on. The CPU is executing or ready to execute instructions, PCI activity is full, AGP activity is full. RAM is being read from, written to or refreshed. Hard disks are on.
S1 "Power On Suspend/Stopgrant" MS: Standby
The system is turned on. The CPU is not executing and is not ready to execute instructions, although registers and caches are maintained. Devices signalling support for S1 are in the on state, devices without support for S1 are in the off state. RAM is idle, but refreshed. Any device currently in S1 with support for resuming may resume the system (WOL, WOR, keyboard, mouse, timer, etc.). PSU state is on. Hard disks are off in this state and all states deeper.
Confusing "common" names. S2 is quite logically an intermediate between S1 and S3. RAM refreshes normally. The CPU is in state much like S3. In fact, this is pretty much S3 but with a faster RAM refresh.
S2 is in the spec, but not usually implemented.
S3 "Suspend to RAM" MS: Standby (if notified by BIOS)
S3 often needs enabling by jumper on the motherboard or by support in BIOS. The CPU is not executing instructions, is not ready to execute instructions, does not maintain its registers and does not maintain cache. The OS must flush dirty pages from the cache when S3 is entered. Devices able to support S3 and are enabled for resuming, may resume the system. PSU state is off, system RAM is refreshed (at reduced refresh) using 5Vsb. External peripherals (keyboard, mouse) may or may not be able to resume the system, depending on what their host controller does.
S4 "Suspend to disk" MS: Hibernate
All hardware is in the off state and maintains no context. The system may only be resumed by timer or other hardware resume devices (such as WOL or WOR), but not by interrupts. The contents of RAM are saved to disk and replaced on resume. The PSU is in the off state. Power may be mechanically removed without ill effect.
Note: S4BIOS is a variation of S4 wherein the BIOS reloads the image and not the OS boot loader. As NTLDR is S4 compatible, this is generally used with other OS'. Linux S4BIOS support is "experimental". Note also that using Windows2000 or XP with grub or lilo WILL break S4 support.
S5 "Soft-Off" MS: Hibernate
All hardware is in the off state and maintains no context. CMOS is maintained by 5Vsb, as in S4. The PSU is in off state. Power may be mechanically removed without ill effect.
Have you tried the "...to break a 'boot-loop'" procedure in the 'sticky'?
Not tried, but yesterday had no reset loop. Everything seemed to be ok, but red acpi led S 4/5 still lights when computer is turned off.
Once again, this is not a problem, this is completely normal - 'S5' ISOFF!
"All hardware is in the off state and maintains no context." This means there is no 'restore' state, nothing in RAM, nothing 'pending'...
"CMOS is maintained by 5Vsb" - or, if the PSU is off or unplugged, by the CMOS battery, until it is 'empty'
"The PSU is in off state. Power may be mechanically removed without ill effect." ...meaning you can 'pull the plug', and it won't matter! wait, wait, I had a thought - if you pull the plug, all that will happen is the blessed S5 monitor LED will be extinguished!