Very slow/Unplayable, please help

Hi, I bought Oblivion yesterday on disk and I haven't been able to play it yet. (Sorry for the long post but I wanted to give you all the info I have)

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My System Specifications (as scanned by Windows XP Game Advisor)

Processor AMD Athlon(tm) 64 2200MHz
Display Card NVIDIA GeForce FX 5500
Memory 1024MB
Operating System Microsoft Windows XP
Free Disk Space 114.33GB
Display Card Memory 256MB
Display Driver Version 7.1.2.0
DirectX Version 9.0c
Optical Drive CD/DVD
Sound Card C-Media Wave Device

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When I start it up (I have selected the lowest quality settings) the Bethesda video is reeeally juddery so I skip it and then the Oblivion IV video thing runs fine, as does the 'new' 'options' etc screen. When I select 'new' the movie of the old man is really slow and jumpy so I skip it. When designing my character the mouse lags and jumps around the screen so that was very hard going. Then when the actual game starts it is so slow there is no chance of me playing it.

I have looked at the Technical Support post, but all of those computers with my problem have low spec and my computer is quite new and supposedly high spec (I didn't get exactly what I asked for from the guy building my PC so I don't know, but he told me it is the same). I have deleted a lot of stuff off my PC but I doubt this was the problem since my two 150GB hard drvies have around 90% free space.

Please help me otherwise I'm going to have to return the game

Thanks Gordini! At the moment I have an NVideo Geforce 5500, what would your recommend I get?

Well, that very much depends on your budget. I myself prefer nVidia cards, and if you have enough to spend, I'd get a GeForce 7900GTX card, but they're pretty pricey.

Had the same problem with my AMD Athlon 3000 with 5700 videocard. Bought a n6800 (200 euro's) A major difference. Now I play the game in high quality.

Ooo thanks The ATI x1600 looks promising. Are you sure it will work Koloth?

And by n6800 do you mean nVidia or ASUS?

Yes I am sure it will work. I am running the x1300 on a lesser system and I get very decent FPS on high settings. I had to do a few minor tweaks due mostly to my processors age but the video card was my savior.

And the x1600 does come in AGP if you don't have PCIe.

Thanks for the tip SirGrotius! And a huge thank you to everyone who has replied so far, you've been a great help.

Someone has recommended to me the ATi Radeon X800 GTO so I've compared it to the x1600 on this site http://www.gpureview.com/database.php and it seems better in some aspects but not as good in others. The difference in price doesn't worry me.

Which do you think would do the job best?

(Also, someone in RL has just told me that I need a 512mb though I don't see how this can be true)

quote grumpygrim1

(Also, someone in RL has just told me that I need a 512mb though I don't see how this can be true)

It's not, they're an idiot.