Whats the cause of the problem

Ok I have a couple of issues here and Im trying to determine the cause so Im hoping someone here might have some clues.
First problem - A few days ago I bought a new HD tv with a vga socket on it to use with my pc. It works great as a tv and my PS3 works fine through the HDMI socket, but every time I plug in my pc I can see everything untill I get to the login screen then the screen goes blank and I get a small banner going across the screen saying invalid format. Ive tried connecting it to another pc with the same result. The manufacturer insists the problem is with my pc - that the resolution is to high. I cant accept that as Ive tried it from every resolution from 800x600 up to and above 1024x768 - same probelem every time. The pc Im using at the moment wont even get that far. However with my original pc (when it was working) if I connected it to another monitor and started it on that then plugged in the new screen it would work on those settings. Odd but I cant see why.

second problem - My main pc has blown its gaskets. Well not quite but it feels like it. I was havng problems with windows starting. I t would get as far as the splash screen and then when it is supposed to go to the login screen the screen would go blank and my keyboard would get turned off. If I waited a while it sometimes came back on and I could then login as normal. However yesterday it just point blank refused to come back on. I assummed windows had fouled up so I decided to do a restore - no joy. So I then went for a full reinstall and that is when things went pair shaped. First off it refused to reformat the harddrive so I thought - ok the HD has gone up the spout. So I put in a new HD. It appeared to go beyond the format stage to actually install the files - but thats as far as it got. I tried it several times and each time I less and less done till I didnt even get the options screens up to choose language etc.
At this point I put the pc on the bench and had a look at it. It was a bit dusty but not excessive. I thought maybe the heat sink fan was playing up so I attached a different heatsink and fan. NO go same problem. I've tried changing the DVD drive - the graphic card and even done a memory check - all seem ok as nothing seems to change the outcome. Im now presuming that either the M/board has gone and or the cpu.
Any thoughts on this?

Go to the manufactures site of the hard drive and find a utility for checking the drive - how long ago did you check the memory I had similar results - if one stick goes it can take several weeks - it seems like the hard drive, but its the errors on the hard drive caused by the memory getting worse. The whole thing gradually gets worse till it wont boot. As far as the hdtv is concerned bing its name, and find the manufactures site - support - find its specs, manual etc and see if they are telling you the truth. Peace of mind + you should find some helpful info, hopefully. If you have already exhausted this angle post the name of the hdtv someone here might have some ideas.
It connects thru the video card, correct? Have you tried the latest nvidia W7 drivers - http://www.nvidia.com/Download/index.aspx?lang=en-us

Antony said:

A few days ago I bought a new HD tv with a vga socket on it to use with my pc. It works great as a tv and my PS3 works fine through the HDMI socket, but every time I plug in my pc I can see everything untill I get to the login screen then the screen goes blank and I get a small banner going across the screen saying invalid format....

Have experienced the same with a Sony Bravia TV set, and it's the TV which is to blame when your graphics adapter can output fine to other screen hardware - and I agree, there's absolutely no rhyme or reason to it (except poor technical design!) but I did manage to overcome the issue with a simple three lettered approach...

RMA...

OK - now I am more confused and rather more concerned. Let me explain what Ive done and maybe somone can tell me what is going on.
First off I decided to check the memory chips again. I have a total of 4Gig in 2x2gig chips. I took them out one at a time and checked each one in both slots then tried to reinstall 7. No joy I continued to get to the same place and then nothing.
So out of curiosity I thought to myself - what would happen if I tried to install a different OS? So I dug out my old XP disc dropped it into the drive and rebooted. HEY PRESTO!! guess what? a perfectly straight forward install - no hassles and fully operational. To add insult to injury the new screen is also now curiously working too!!!
So what is 7 doing? It refuses point blank to reinstall giving the impression that there is a hardware failure. Being able to reinstall XP has proved that the problem lies not in the hardware but in 7? Is this a new issue? Are other folk having simular problems? The version of 7 I have is the ultimate as supplied by MS for those of us who hosted the Win 7 parties just before it launched. Is this a crippled version despite us being told it was the genuine product? I had been running the 64bit version - I did try the 32bit version and had no success with that despite the fact that the disc had never been out of its packaging. Has 7 done something to the bios to prevent it being reinstalled? I just dont know. Im confused. Can anyone shed any light on any of this at all? (Oh and yes this is being written on the said pc running XP).

I thought Id update this with the latest developments.
Since I had gotten XP working I was certain it was not a hardware issue (I now own an additional drive I need not have purchased). So I began asking myself what has changed? certainly nothing I had added to the system. If XP was now working on the new hard drive - proving no hardware failure - I assumed that the old drive was also ok. Which bought me back to the question again - what had changed? I began reading some of the posts in the installation section on this forum and decided to do as one of them instructed with another problem - that was to reset the cmos to factory default.
I plugged in the old drive dropped in the win 7 install disk and proceeded to install 7 without a problem on the old drive.
So the question I am left with is why did windows 7 install have an issue with the cmos? What did it change? I really dont have a clue to it but I do know that resetting the cmos has resolved the issue. At the end of the day I think I should have put this thread in the software section not hardware - but I was convinced at the beginning that it was a hardware issue. I guess in one sense it was but not the one I expected. Maybe my problems will help someone else who comes across this issue.

Oh nearly forgot. The new screen. It still refused to work with Win 7. Conclusion it was not compatable. I contacted the company and the manager there acknowledged that the tvs had not been tested with Win 7 and he would pass that on to the techies to deal with. The store I bought it from gave me my cash back so in the end I didnt lose out.

Well done :)