Many will have read the trials and tribulations I've had with graphics card failures followed by PSU failures and it seems my days of woe are far from over.
It all started with the 8800GTX letting go. I replaced this with an Asus GTX560Ti and the system ran for a day before the PSU gave up. Having sent the old one to Holland, a new one appeared a few weeks later and was installed. Initially, the system didn't POST so I used the mobo reset button (Asus P5Q deluxe) and it fired up fine. It fired up fine the next day but the following day it didn't. I tried various things to get it running and eventually, it did though by this time, I couldn't remember what combination of things I'd done. On reflection, I don't think my fiddling did anything.. it started because it was ready to start (by start I mean POST). Over the next few days, it became increasingly difficult to get it past POST so over the last weekend, I sent it into standby instead.. something it did fine and fired up the next day.
I went up to the Midlands on Monday and returned on Tuesday evening and not wanting to leave it in standby while I wasn't here, I closed it down. It has not achieved POST since. I don't have a great deal plugged onto the board.. 2 SATA drives, the GTX560Ti, a new SATA DVDR, wireless adapter, joystick, Creative speakers, keyboard/mouse, 2gb Crucial Ballistix ram and 3 case fans. The replacement PSU is an updated version of the old one.. a Corsair TX650v2. That's the lot. Not a great deal is it! Oh.. and an intel E8400 cpu!
When I hit the on/off button from cold, the red HD light flickers once.. the pwr light comes on.. all the case fans run and there's visible indications that the GTX560 has pwr (2 green lights) and the mobo is powered (onboard on/off and reset buttons lit). In desparation, I've cleared the RTC CMOS to see if it would rebuild/return the CMOS to standard/default settings but this has had no effect.
Before I throw the lot through the nearest window, does anyone have any suggestions? I've not removed the graphics card or ram yet but I have removed/disconnected all drives (inc the DVDR) and the system refuses to post. I guess the next step would be to remove the graphics card and ram.. in fact, everything to see if the board will POST or at least give me a fail indication (number of beeps during POST).
ATB
DaveB
The mobo is only a couple of years old so it shouldn't really fail but you never know. I've been wondering if the GTX560Ti hasn't got something to do with it. I'm sure I read somewhere on one review that 'starting' had been reported as an issue but I thought I'd get past that by having an Asus mobo and graphics card. I dunno.. it doesn't make a lot of sense. Still.. it's sitting there doing JS at the moment so I'm willing to try anything 
There is a web site that lets you calculate the size of the PSU, are you overstreaching the existing one? Does the new card need more current than the old one? The web site was part of a thread on this site some time ago (maybe 18 months) if that helps you find it. You always need about 25% more than you need as far as power is concerned.
