Your power supply can still be in perfect working order but still not push enough watts out to run your entire system at once. It used to be that not everything ran on the 12V rail, CPUs were 5V for example, mostly just drives with spinning platters needed 12V, these days nearly everything sucks power off your 12V rail; so even if an older PSU pushes in theory enough watts to run everything in your system, it might not push enough on your 12V rail.

I'm still not clear how you found a vid card to go in your PCI slot, but I guess they must still exist. I don't know what kind of cash you have but you can buy a replacement gaming quality ASUS mobo for well under 40 bucks for that old of a CPU, it won't have a PCIe slot but you won't need one for whatever vid card you choose.

Before you spend cash take a slow trip through your BIOS settings with the manual to make sure you don't just need to tweak something to make your board work well with a vid card in a PCI slot. Also, it never hurts to reseat a misperforming piece of hardware, I've had RAM poorly seated before, ground yourself on something metal, take it out, blow hard on the slot to remove any static charge remaining and put the card back in. Sometimes you have a bum slot, you may try another PCI slot when you are playing around.

The Radeon I have installe d is an AGP.

And my BIOs doesn't offer a whole lot of options. For instance, when it comes to video, it only allows me to select either 'AGP/Onboard' or 'PCI' there are absolutely no other tweaking options.

I've got warn anyone ever looking to purchase a new system to go custom through mum and pop locals and run screaming from factory-built like Dell and HP.

Okay.. It's a hard one to figure out.

No matter what the tech says, sometimes it's BS (depending on how lazy they are, etc). Find out the brand of your PSU, which is really important, and what type it is. 500w, 600w, etc.

Like orcishgamer mentioned, relatively unknown brands tend to be very low quality, and the rating they have is usually misleading. An unknown 400w PSU will be crippled by a system whereas a good quality 400w PSU will run fine for many years.

A good tip on the quality of PSUs is actually the weight of the unit. Cheap, unreliable and low quality ones are actually pretty damn light.

It's hard to tell whether it's an overheating or power issue. We don't know if you have run your games one after the other, or between shut downs and so forth.

My personal experience with PSUs not being able to keep up with a system is that the power loss can be intermittent. It can go from failing to boot, shutting down as soon as something is run, or chugging along for a half hour until it reboots.

If you want to check out whether or not it might be an overheating issue, google a tool like GPU-Z and CPU-Z. GPU-Z is excellent for monitoring graphics card temperatures, and the CPU-Z program tends to monitor more than just the CPU.

Also, you didn't mention the operating system?

I know, we're asking for a LOT of information, and a lot of advice is being given. It can be overwhelming, but unfortunately it's the way it is. Trial and error until you can isolate a problem to a more exact area.

I'm using Win XP 32 bit updated to SP3.

I got to the source of the problem. Being a seven year old computer that originally only had a Pro Savage 64mb on board to worry about, HP installed a 250 Watt HIPRO.

It's a good power supply and still functions but is insufficient for the HD 3650 that I've got in this machine.

And this makes total sense.

Game taxes Radeon = Radeon attempts to draw more from power supply = Power supply can't meet demand and sends termination code to mother board to either drop and reboot system or sometimes severe signal between monitor and card.

What was hapening with Spellforce was even though I was just letting the game sit still with hardly anything happening on the screen, the opposition were building more and more units. You would think these would only come into rendering and consideration once you actually stumbled upon them on screen, but taking note of Spellforce, there is no hesitation for load times while traversing the map. That means that even though this stuff is taking place off screen it is still being rendered as if it were already on screen.

So the more the opposition grew, the more my card was taxed and the more that my Radeon had to pull from the power supply. Hence, ten minutes in and a loss of signal to the monitor or a drop reboot would take place.

For what it is worth. Nvidia has even worse backward compatibility problems then ATI.

I've got a completely opposite experience with my NVIDIA cards (GeForce MX200, GForce ti 4200, GeForce 9600M GT).

I can get nearly every game out there to work on my ATI pc, the nvidia PC while faster with better specs plainly sucks ass at legacy games...

possible issues:
Drivers
Over heating
Bad Ram on the GPU
Powersupply
Bios Settings
North/South bridge overheating/failing
MB Ram to hot/failing

If you know your hardware is 100% working then i would just do a clean install of your OS. focus on MB drivers and GPU drivers and run the games with compatibility patches and what not. sometimes old games cant handle new tech, disable all you can, and use driver settings to tweak them for older games. use the half-again proccess.

more often then not advanced direct x tweaking fixes my issues... EG: Blood 2 all it needs is DX tweaks to work right, same with Rune, KISS PSycho Circus, and Shogo... AvP the original only runs on ATI drivers due to them supporting older code instructions

I forgot I created this thread. Lol.

I found the issue.

The Radeon requires at least a 300 watt max output from my PSU. My PSU's max output is 250 Watt. Considering that my PSU is seven years old, it's probably only maxing about 175 Watt now.

What's confusing me though is that my older Geforce 5200 can run these games really good and I would assume that the Radeon would only pull power, when power was needed but titles like Spellforce and Bloodlines seem to take note of the Radeon and drain it for all it's worth where as my Geforce they must be acting a lot more conservatively with.

Which is funny, AMD/ATI graphics run cooler than Nvidia graphics usually... glad you found it... ive had that "facepalm" moment before when all i needed was a new PSU.

Well, even with the new Cooler Master Dual Rail 460 installed, I've had the somewhat of the same issues with the same games with exception of Spellforce.

Spellforce works fine now on lower eye candy and no longer loses signal to the monitor or does a dump reboot.

But I was still having problems with X Blades crashing in the menu screen and Bloodlines makes my computer either dump reboot or scream.

If I can get in the actual game in X Blades, it works fantastic.

So what I come to find out is that I had the latest Radeon Hot Fix installed when I didn't need it and I've also heard a couple of people mention that the newest HD3000 series drivers are unstable.

It was a mess, man but I finally fixed it. Plug N Play kept loading back shitty Radeon drivers at the same time that I was sweeping them in Safe Mode. Turning off Plug N Play in BIOs and services didn't help either. I just gave up, let them install and then overwrote them with the drivers that came on disc with my card.

Also the older version of Catalyst on my disc had SmartGart which the newer version of Catalyst didn't.

For the past five hours I've been running great on old drivers.

With X-Blades, there's something about the FMV sequences that don't jive with my rig. My LCD goes up to 1280x1024 max. If I didn't escape through cutscenes in time the FMV would hang and I would get the dump reboot. So I put on the option in Catalyst for it to try and rescue failed video and I set Win XP to not reboot on a system fault.

And that fixed it. Now the cutscenes will lock up but I've got all the time in the world to hit ESC and get into the game.

The only three out of my games that are unplayable now are some stupid Dragon game (forget the name - it was on sale at D2D for $6 last week), The Masquerade: Bloodlines (which I don't think works for anybody period) and Scrapland....erm...of course I haven't tried Scrapland with everything cleaned up but previously it was a dogshow.