What upgrade is the best option?

Hi all,
Its time to upgrade for FSX but what would everyone recommend as an ideal upgrade on a limited budget in terms of getting most bang for my buck?
Specs
Asus k..... motherboard (cant remember seriel)
Athlon 64 3000 socket 754
Radeon 9800pro 128mb card
2x 512 3200 Kingston Ram
1x 250GB SATA Western Digital HD
1x 80GB Seagate HD
500W power supply
I thought maybe another gig of Ram or maybe my graphics card is slowing me down. I dont really want to replace the motherboard or processer unless I get a second hand 754pin AMD to go in my current board. I dont know if id be wasting my money in upgrading to a 3400 or 3700?
Thanks
Its time to upgrade for FSX but what would everyone recommend as an ideal upgrade on a limited budget in terms of getting most bang for my buck?
Specs
Asus k..... motherboard (cant remember seriel)
Athlon 64 3000 socket 754
Radeon 9800pro 128mb card
2x 512 3200 Kingston Ram
1x 250GB SATA Western Digital HD
1x 80GB Seagate HD
500W power supply
I thought maybe another gig of Ram or maybe my graphics card is slowing me down. I dont really want to replace the motherboard or processer unless I get a second hand 754pin AMD to go in my current board. I dont know if id be wasting my money in upgrading to a 3400 or 3700?
Thanks