js6969

Sorry if this is a long one but I gather detail helps you guys to help me. Having researched some similar posts I think this may be a PSU problem but wonder what you think.

Until 2 days ago I was happily using an nVidia 7900GT graphics card. I shut down overnight, then the next time I booted up in the morning I couldn't get anything on the monitor - only a message saying "no signal". Nothing had been altered at all, just shut down and turned on again, as usual.

I tried various things including a different monitor, different cables, different DVI slots, all to no avail. Thinking that the 7900 card had died, and now having an excuse to upgrade to a new card, I coughed up and ordered an XFX Alpha Dog 8800GT from techheads.co.uk .

However, on receiving and installing the 8800GT today I have what appears to be the same problem. The first time I booted up I reached the screen giving the 'tab / del' options to enter post or setup. Here, everything froze. Re-booting 2-3 times it did the same or a very similar thing, getting no further than the 'start in safe mode or use last known satisfactory setting' page where it froze again. Further re-boots gave the original 'no signal' message. Then, once, I managed to get it to start in safe mode, where the desktop appeared. I was just about uninstall the existing video card drivers via the control panel (couldn't do it before because I'd lost the monitor image, hence trying the new card). Then the 'found new hardware' wizard appeared and before I could do anything, the whole system froze again.

This was the furthest I ever got and since that time, any other re-boots / switchings on and off just give me the 'no signal' image on the monitor. This was where I was when the problem first appeared with the old 7900 card two days ago.

I've tried disconnecting both case fans to reduce power consumption but that had no effect (and anyway, the XFX box says a 500W PSU like mine will run the 8800GT in non-SLI mode).

There is a six pin power connector on the 8800GT card. I have it connected via an adaptor from a regular 4 pin power connector from my PSU. This worked fine with the 7900 card for 1 1/2 years. I then saw that XFX's manual says that you should only use a 6 pin connector straight from the PSU and not going through any 4 to 6 pin adapters. Is this the problem?

Or is it a PSU failure that has affected both my cards, the old one and the newsest one?

Or has the PCI-E slot on the mobo just died on me (although the board's only 1 1/2 years old)?

My PSU is a 'COLORSit' 230VAC, 10A 50-60Hz and 'on the tin' it says:

+3.3v 28A
+5v 35A
+12v 25A
-5v 0.5A
-12v 0.8A
+5VSB 2.5A

Any ideas to help, please?????


Athlon 64 AM2 3800+ 2.4Ghz, 2 Gb ram, Abit KN9 SLI PCI-E mobo, Win XP SP2, graphics cards in the PCI-E x16 slot.

js6969

Sorry, forgot to mention that the PSU is 500W.

dai

your amps on the 12v+ line needs a min of 26a,so the 12v line has probably deteriorated and no longer supplying enough amps
colorsit is only classed as average,see if you can borrow a quality one to check with
if you buy go with a quality 650w
Power Supply Information and Selection

js6969

Thanks dai. I'll have to buy a new PSU, but given my future planned CPU upgrades it won't be a waste either way. Just to check something - the deteriorating 12v line - that would been why both cards stopped working? Have I got that right?

Cheers.

dai

yes the common factor between the 2 is the psu,if it was the adaptor only you would expect the other one to work

js6969

It'll take a few days to order and get a new PSU - I'll update afterwards with the results. Thanks.

js6969

I managed to borrow an Antec neopower 650 blue psu (almost new). 3x +12v rails, 19a on each. When fitted and the computer was turned on, it went to the post screen the first two times and there was no longer a 'no signal' message on the monitor, but nothing else was shown on the screen (as per the usual windows log on process). From then on there was no joy. It wouldn't post and reverted back to the 'no signal' message. All leads and connectors re-fitted and re-tried without success.

Any ideas??????

js6969

Right, something new tried. I removed the graphics card and reset the CMOS (battery removed for 30 minutes). When restarted with the graphics card re-inserted, the monitor fired into life and got as far as 'press F1 to continue of del to enter setup'. I pressed F1. Then, as per my update tonight at 0727h GMT, there was no longer a 'no signal' message on the monitor, but nothing else was shown on the screen (as per the usual windows log on process). I can see the monitior is working, it's got no 'no signal' message, the monitor is 'dark' with no image but isn't comepletely black, and hasn't reverted to standyby power mode. Just no picture.

js6969

Still trying... I reset the CMOS again and it posted. I hit 'del' to enter setup and the BIOS screen appeared OK. PCI-E was enabled as the primary graphics feed. There are no onboard graphics on my mobo so it's not clash there. When I exited the BIOS, it went back to the 'no signal' message again on the monitor. Why does that not surprise me?

dai

check if you are getting a screen in safe mode
when resetting the bios are you doing it by using the cmos jumper as well as removing the battery with the power disconnected

js6969

Oops, noob to CMOS resetting so I have now tried it again with the jumper (as per online ABIT KN9 SLI manual). I got back into the 'press DEL to enter SETUP' screen and made sure the defaul settings were in there. I'd not changed any of them since I bought the computer and certainly not at the time this overall problem started. It hasn't solved the problem, I'm back to the 'no signal' message.

The screen allowing me to enter the BIOS / CMOS didn't look like a safe mode one, from past experience. There was no 'safe mode' or 'use last known reliable settings' options and no countdown clock to choose anything.

I have a photo of the first screen I see (white text on black, details the BIOS, processor, IDE Channel 1-8 master and slave disks, press F1 to continue or DEL to enter SETUP, at the bottom of the page). I'm new to posting so can't see how to include it in this post. If it would help, please can you advise me? This first screen does say "CMOS checksum error - defaults loaded" each time I've reached it after tinkering with the CMOS resetting. I take it this is because of the re-setting?

dai

you have the aux power plug connect to the m/b

js6969

Yes. 4 pin CPU, 24 pin MoBo, PCI-E mobo Molex and graphics card power plugs all connected.

When the fault first occurred I had 2x 1GB sticks of Kingston KVR533D2N4 1.8v RAM fitted, in slots 1 and 2. In case a stick had failed I removed the slot 2 one and tried both sticks on their own in slot 1. Still getting the 'no signal' message.

Incidentally, there are no beeps when the system powers up each time. Is that a good or bad thing?

Also, given that I am intermittently getting the BIOS screen, I take it that the PCI-E x16 slot I'm using is fine because, with no onboard video, the graphics card must be becoming active for me to see the BIOS screen? I can't fit the 8800 GT card into the second, PCI-E x 4 slot due to the board layout. However, I've tried the 7900GT card in that slot (I'm assuming that card was originally OK because of the way this problem has developed) and it still doesn't get into the BIOS screen, just 'no signal' again.

(PS... Whilst I am still Ok trying to sort this out and have my wife's laptop for this forum (thank heavens!) and other day to day stuff, I'm wondering if I shouldn't just bite the bullet and upgrade to a new MoBo and intel Core Duo E6750 (from Athlon 64 3800+). Although, if I have changed the Mobo, graphics card, power supply and chip would that mean it wouldn't recognise my current registered Windows XP OS? I've heard that too many hardware changes can mean your current Windows OS doesn't work because it thinks you have transferred it to another computer without getting a new licence).

dai

no post beep is not a good sign
set it up out of the case on a piece of cardboard with
cpu
video
ram
speaker and see if it posts

js6969

Sorry Dai, but I lost patience with trying to work out what was wrong in the end. Decided to bite the bullet and upgrade earlier than expected. Now I have an Intel E6750 CPU and Asus P5KC MoBo combo that works well. I am thinking that my old Abit KN9 SLI mobo was a bit knackered in the end, causing this video problem. C'est la vie.

dai

i am running a similar setup