IMy pc is a HP a420a Pavillion http://h10025.www1.hp.com/ewfrf/wc/prodinfoCategory?lc=en&dlc=&cc=us&product=385639&lang=and at the moment i'm using a Nvidia GeForce FX5500 AGP video card which runs fine. Now i'm upgrading to a 256mb Sapphire Radeon HD2400 PRO (AGP) http://www.newegg.com/Product/Product.aspx?Item=N82E16814102734 so i can display my maximum resolution on my new 1080p monitor. I'm just unsure to whether this is going to require more power to run :S on the HP website is said something about my PSU being 250 watts. http://partsurfer.hp.com/cgi-bin/spi/main?sel_flg=partlist&model=DT063A&HP_model=&modname=Pavilion+a420a+(Asia+Pacific)&template=main&plist_sval=Power+Supply&plist_styp=subcat&dealer_id=&callingsite=&strsrch=&keysel=Power+Supply&catsel=%3F So if anyone has any knowledge on PSU's or can find any information on this new graphics cards power usage compared to my old one i would appreciate your help 
ty 4 any answers
Um...yes.
The HD class cards (being less than 2 1/2 years old) draw a LOT more power than your current card, which is about 6-7 years old.
That being said...you may be SOL (and I don't mean the Sun). I don't know if it can run a 1080p monitor at it's native resolution...and quite possibly NOT at high-def. standards. If you'd mentioned the HD2600, I'd be quite comfortable in saying you probably could use the 1080p monitor to it's fullest advantage.
Outside that. Being a 6+ year-old computer, the motherboard may not be able to handle the card even if the PSU can power it...which it may not (probably can't) be able to.
Try going to the ATi (aka: AMD.com) website and look into the stats on the HD2400 Pro. It will answer EVERY question you might have about your card. (Incidentally, even if it is not an ATi produced card, because it is an ATi model, you can register it with ATi for full product support!)
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