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Arcade VGA FAQ

I use an arcade monitor. Why do I need a special card? I thought ordinary VGA cards can work with arcade monitors.
Yes it is true that some older cards can be configured to output a15Khz horizontal scan, by using special drivers, or by functionality built into applications such as Advanced MAME. This has always been a problem area though.Advanced MAME is notoriously difficult to configure. Also you can never really be certain that your card will work at all, at 15khz. Even if you can get the card to display 640 X 480 at 15Khz that is nowhere near the capability ofthe ArcadeVGA since there are 30 other lower resolutions available when using this card. Sometimes even cards with "known good" chipsets will not work owing to having a different OEM BIOS. Most standard cards will not allow the pixel clock to drop low enough for low resolution modes such as 320 X240. The boot and DOS screens can never be displayed correctly using ordinary cards. Often hardware stretching is required. The ArcadeVGA card allows a no-hassle way to emulate the video logic of an original game board without having to use any special drivers or configuration, and, for the first time, also allows this to work in Windows.

I only use a conventional PC monitor. What is the benefit of this card? My ordinary card seems to work fine with MAME.
When you run most MAME games, a process called Hardware Stretch is used. This is needed because most arcade games do not use PC resolutions suchas 640 X 480, 1024 X 768 etc. They use resolutions such as 256 X 264. These arcade resolutions could not, until now, be displayed in Windows on a PC monitor. To get around that problem, MAME tells the VGA card to stretch the image to fit the PC resolution. This means that the pixel-to-pixel mapping of the original game onto the monitor screen is lost as there is no longer a one-to-one relationship between the pixels which the game designer created and the displayed pixels. As arcade game resolutions are generally low, this creates a loss of quality. It is important to note that using a PC monitor will NOT produce an arcade monitor-like picture as PC monitors have a much higher dot pitch and finer scan width than arcade monitors. But using the ArcadeVGA will give a crisper picture than an ordinary VGA card, at the lower resolutions. There are some comparison pictures on the product page. Another benefitis that the vertical refresh rates of the ArcadeVGA modes are tailored to Mame games which means a smoother motion on horizontally moving graphics.

What are the differences between this card and a normal VGA card?
All VGA cards contain a number of in-built video modes, that applications can detect and switch to. The problem with normal cards is thatall of these modes are useless on a 15Khz monitor because they all send a 31Khz horizontal scan rate signal. Even if they could be used, they are not tailored to gaming because most of them are a too-high resolution. When used with an arcade monitor the ArcadeVGA card discards all of these modes and replaces them with an enlarged set of 30 built-in modes, all of which send 15Khz and all are tailored to gaming. The mode timings are held in flash ROM on the card. The pixel clock circuitry is different to allow for a lower value of clock, needed for lower horizontal scan rates. With a PC monitor all of these modes are also available but they scan at 31Khz. In addition, on a PC monitor conventional Windows modes are available.

What about boot screens, DOS prompt etc?
On an arcade monitor, the standard VGA modes, used in booting and DOS etc, have been replaced by modes with the same resolution but at a 15Khz scan rate, so all screens, right from power-on, are displayed perfectly on an arcademonitor. The card dynamically calculates and adjusts the pixel clock to produce the correct 15Khz scan rate.

But how can I get a full DOS text screen on an arcade monitor which can only display half the number of lines?
The easy way to have done this would have been to simply enable interlacing for DOS text screens. But we did not do this because an interlaced picture is not really satisfactory for text. So we replaced the built-in text fonts with smaller ones to be able to display all 25 lines without interlacing.Result: a perfectly clear text screen with no flicker.

What about Windows?
When you plug in the card and start Windows, it will immediately display the desktop on your arcade monitor. Then, after loading the drivers, the full power of the card is unleashed. The 28 built-in gaming resolutions areall available for selection for perfect arcade quality on your arcadeor PC monitor. On an arcade monitor, the Windows desktop, by default is displayed at 640 X 480. Because an arcade monitor can only display a maximum of 300 lines, we have to interlace this picture. It is true to say that theWindows desktop is not ideally suited to interlacing as it has single-pixel lines, which interlace causes to flicker at 30Hz. So there are alternative resolutions you can switch to, which are non-interlaced, such as 640 X 288. In addition, in Windows XP, 2000 and Vista there is an "auto-pan" mode in whichthe desktop resolution can be greater than the monitor resolution. These restrictions dont exist when using a PC monitor of course.

What configuration do I need to do?
To get the best results, you may need to select and save a suitable resolution for each game because the MAME "auto" resolution does not always pick the best resolution. There is some configuration in Mame to do, to turn off hardware stretch and direct 3D. This is detailed on the installation page.There are also helper applications which will automatically create configuration files for all games, containing correct resolutions.

Will other (non-emulation) applications work?
Yes. In Windows, on an arcade monitor, any game or other app that will run at 640 X 480 or 800 X 600 should work fine. These resolutions need interlacing owing to the arcade monitor limit of 300 lines. However, 3D games etc produce a good picture with interlacing. Some older DOS applications tha tuse custom text or control the card's registers directly, may not work. This type of application is rare nowadays. PC monitors dont have any restrictions of this kind.

Can I say goodbye to Hardware Stretching for ever?
Almost all games will never need this option and will display at their original resolutions with full arcade quality. But there is a range of vertical resolutions that arcade monitors cannot display. (this is a limit of the monitor, not the card). The range is from 300 - 450 lines. This range cannot bedisplayed because the figure is too high for non-interlaced display and too low for interlaced (without unacceptable top/bottom borders). So games with 300 -450 vertical lines will still need H/W stretch to fill the screen.

What if I have a D9800 or other multi-frequency monitor?
The Wells-Gardner D9800 monitor is an example of a multi-range monitor that can display all arcade modes from 15Khz right up to 31Khz. The ArcadeVGAcard makes a perfect partner for this monitor, because it enables you to use the 15Khz modes which a normal VGA card would never use, unless you used Advanced MAME. In fact unless you use a method to enable 15Khz modes, you will have wasted the extra cost of the monitor over a standard VGA monitor. There is a special software utility for the ArcadeVGA card which unlocks the 31Khz resolutions so you can run Windows at it's normal non-interlaced resolution instead of 15Khz interlaced. 25Khz modes are also supported.

How do I connect the monitor?
PC monitors simply plug in as normal, to the DVI port, using a DVI toVGA adaptor if required. If you are using a J-PAC JAMMA interface with an arcade monitor, just plug it in. If not, you can connect a VGA cable to an arcade monitor directly. The ArcadeVGA card produces 1 volt signal level output.Wells-Gardner, Hantarex and many other monitors can accept this directly. See here for more connection details. We also sell a connection VGA cable which has a Wells-Gardner connector and also has wire ends labelled for easy connection to other manufacturers monitors. Some arcade monitors may need our video amp PCB,unless you are using a J-PAC which has an on-board amplifier. This now includes an attached VGA cable to plug right into the ArcadeVGA card and needs no separate power supply when used with this card.

Why don't we supply a cable with a plug on the monitor end for all monitors?
The problem is, there is no standard for arcade monitor connectors, sowe would not know what type of plug to fit on the other end. So, unless you are using a J-PAC, there will be some simple wiring to do. Our Video Amp also acts as a "break-out" which makes the RGB and Sync available on screw connectors,making the connection easier. We do sell a cable with a connector forWells-Gardner arcade monitors as this is the most common brand. This cable can also be used for connection to other models as the wires are labelled.

What about Composite sync?
The ArcadeVGA card is designed to be connected to either a H-V sync or composite sync monitor. All video modes produce negative H and V sync. Thismeans that the H and V sync wires in the VGA cable can simply be connected together to produce composite sync, if you are making your own connections.

Do Optical Light Guns Work?
The Act-Labs USB gun works but there are some factors to bear in mind.The gun will only work if the H and V sync are not connected together.The H and V signals must both be connected to the monitor. OR, if a J-PAC is used for the connection, this will also work. Our own AimTrak gun is independent of the monitor and will work.

Apart from the arcade monitor functionality, what are the card specs?
It is based on an ATI Radeon RV630 chipset and has 512 Mb RAM. This high-performance card is guaranteed to run SF4 at 60 FPS at full detail graphic settings. AGP Radeon 9200 card (128Mb) available while stocks last.

What operating systems are supported?
The card supports boot screens plus Windows XP (32 and 64 bit), Vista (32 ans 64 bit) and Windows 7 (32 and 64 bit). No other OSes are supported.

Anything else I need to know before ordering?
Make sure your PC has a PCI Express x16 slot. Note PCI is not the same as PCI Express.