Hi, I'd like to upgrade my video card from a 125 MB to a 512 MB.

But I am unsure as to what my system can support.

I know that I have a PCI-E slot on my motherboard, so I am looking with cards that are compatible with it.

I know that I have SLI-E capability, so it is always an option.

I am unsure as to whether my power supply provides 300 or 500 W of power, but I do not think that it is that big of an issue, unless I am using dual graphics cards.

If there is anything else that i should watch out for, can someone let me know?

My PC model is a Sony Vaio VGC-RB54G if you need to know.

Thanks.

According to Sony support...
That mobo has one PCI x-16
and one PCIx-1 slot---which means no SLI
SLI requires Identical cards and Identical slots.
That's a 300W PSU-- not 500--
If you think about changing PSU's-- Sony's are tough-to-fit ... if I recall correctly.
Many off-the-shelf PC's don't use standard-sized parts

ah, thanks. I had thought that I could use SLI E. A friend at school told me to look for the cable which he descirbed for me.

So 300 W is bad? Do you think that i won't be able to run a 512 MB card?

Apart from those, is there anything that I should look out for compatability wise?

Your friend give you a website for this cable ? Just curious.

300w is not "bad"...per se-- one card should be OK.
It could be trouble running 2 cards-- and as I said-- to upgrade an off-the-shelf PC is sometimes tough-- I have never worked on a Sony product-- but makers tend to use many small "tricks" to control their costs.
Whether an after-market PSU could be mounted in a Sony case-- I really don't know. The only way to know is to measure the current PSU's dimensions-- and double check everything first.

I see... Thanks a lot then.

So about graphics cards, I've been looking around on ebay.co.uk for some deals. A lot of them say that they are 512 MB, but only 256 MB is onboard, and the rest it draws from the RAM. My dad suggested getting one of those and then upgrading the RAM. But my friend told me that those were far less efficient than getting one where all the memory is onboard.
Is this true?

But he also said that 512 MB doesn't say much in some cases. He said that one that has the same memory could be far better than the other-because of how the card is designed...
How am I to know which ones are good and which are bad?

He reccomended an Nvidia Geforce 8800 (512 MB) but the prices look a bit out of my price-range, and pounds are worth a lot more than euros.

Yes-- System RAM and VRAM or video-ram are different. Same basic idea-- but Video RAM is dedicated to one purpose--Rendering Video.
System RAM operates the whole PC-- so if you share it to run graphics-- that slows everything else, to some degree.
Top-of-the line cards are expensive... you might be able to get by with an 8600GT-- I'm no major Gamer-- I could ask around for more opinions.

True also-- to some degree...
I'm not trying to discourage you-- but if you want a hot-rod gaming machine-- you'd be better of to save your money and build it from scratch.

More info than you can stand-- is available for free here:

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