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Ron Bakker
17-09-2002, 10:43 PM
When talking about video cards main chip, they talk of two diifferent numbers. Why the two different numbers?
Sorry but I am learning slowly :8}

mikep
17-09-2002, 11:20 PM
Graphics processors, like your main system processors are climbing in speed all the time as new models come out. ATI cards boast the graphics processor speed normally as the first figure whereas the 2nd figure is normally the RAM speed. I'm no expert on this technology, but here is my understanding.

For an example, a Radeon 9700 Pro has a GPU speed of 325Mhz & the memory has a rated speed of 310 x 2 = 620Mhz, hence this card is rated at 325/620. Why the greater memory speed? It's because the memory type is DDR SD-RAM, The DDR means Double Data Rate, so in effect, the chips have twice the bandwidth so they can put out twice the data, hence the label 620, but it's not really 620Mhz, it 310 x 2.

There is another figure commonly put ou & that is the RAMDAC (Random Access Memory Digital to Analogue Converter). The same card has a RAMDAC rated at 400. I don't know if it's a Mhz scale or something else, graphics processing is getting fairly intense now as the more work a GPU can take from the CPU, the faster a system can run through freed up CPU cycles. I might be wrong in this, but I think the RAMDAC is only used for standard CRT monitors, not digital LCD screens.

Anybody wishing to clarify this?

Mike P

Ron Bakker
18-09-2002, 08:31 AM
Well you have cleared my main question & given my more of an insight.
Thanks mike.. :D