First off, get Pete's latest Plugin pack (now at v1.72!!), and use OpenGL.
Secondly, use the default CD plugin from ePSXe, cause I get the best performance from that.
Thirdly, use Eternals SPU v1.41 for sound.....again, better sound/perfomance.
You're rig is good enough, so try those out.
ready2rumbelX
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ready2rumbelX
-Intel Core 2 Quad Q6600 (@3200Mhz)
-Gigabyte 965P-S3 motherboard
-2x2GB G.Skill PC-6400 (DDR2 800Mhz) RAM (4-4-4-12)
-Seagate 320GB (IDE) and Western Digital 500GB (SATA II) H.D
-Sapphire Radeon HD 4870 512MB GDDR 5 (850/4600)
-Windows Vista Ultimate SP1 (x64)
-Realtek HD w/ Creative PC Works 5.1
-2 x L.G DVD/CD-RW Combo - GSA-H62N