Windows 7 - Dual Monitor Issue

Hello,
I'm having an issue using two monitors on my PC.

A bit of background info:
Ive been using dual monitors for about a year by plugging one into my on-board GPU (VGA-VGA) and one into my external GPU (VGA-VGA-DVI-I using an adapter).
For reasons which I can't be bothered to explain because it's not important, my on-board GPU no longer works and I must use my two DVI-I ports on my GPU.

Now, here's the problem:
Both screens are identical, with VGA-VGA wires. I am using an official ATI VGA-DVI-I adapter that came with my GPU (NVIDIA GeForce 9600GT) to connect the one screen.
However, I purchased a cheap £1.50 VGA-DVI-I adapter off eBay for the second screen. But my problem is that when I connect either screen with the eBay adapter, it doesn't work properly.

Here's a bit of elaboration:
I can connect EITHER screen in EITHER of my GPU ports using the official ATI adapter, and they work fine.
However, when I connect EITHER screen in EITHER of my GPU ports using the eBay-bought adapter, it either doesn't detect any screen, or it caps me at 1024x786 resolution.
When I go to change my resolution, it calls the not-working one "Generic non-pnp" where-as my working one is called Packard Bell 200Ws.

This leads me to believe that there is an issue with my eBay bought adapter, I just wanted someone to clarify that this is the issue?

I don't want to pay the prices that places like PC World charge for a good adapter, so I want to check here first that the adapter is the issue.

What would you advise?

Also, the adapter is 24+5 pins DVI-I MALE to 15 pins VGA FEMALE.

Thanks in advance,

Gee.

EDIT: Is it possible that my GPU can't run two screens at 1600x900?
The GPU is PCI-E connected, NVIDIA GeForce 9600GT 512Mb.

This is the exact one I bought: http://www.ebay.co.uk/itm/2307245604...ht_5276wt_1163

I'm no expert but it sounds to me like the e-bay bought adapter is missing a few wires that would be used to ID the monitor. If you download the manual for your video card from the manufacturers web site you should be able to figure out what max resolutions are supported. I think its the adapter not a screen resolution problem.

Each screen runs fine at 1600x900 with the official adapter, but the eBay one only lets it run at lower resolutions.

I think thats because the monitor isn't identified correctly so windows only uses the standard video modes. It may think the monitor is smaller than it really is.

How can I be sure that the adapter is one that will work?

If possible, try it on another PC. If you get limited resolutions, you'll know it's the adapter. (Sorry I can't help more, I don't know much about these things )

I don't know, I have several, they all came with video cards I bought, and they all seem to work regardless of what video card I attach them too. What I can tell you is that not all video cards with dual DVI connectors will run two VGA adapters. Sometimes only one of the DVI outputs will actually have the VGA signal on it. The other one is digital only. There is DVI-I (integrated) digital and analog, DVI-D (digital only), and DVI-A (analog only). If your supplied DVI adapter works on both connectors then thats not the case with your card.

Yes, thats a good idea.

The supplied adapter works in both ports, so does that mean that is probably a bad adapter off eBay?

Thats what I'm thinking.