Question about cache

[husker4life]

My new system i got originally had a Western Digital 120gb 8mb cache, it died on me so i had to RMA it. While i was waiting on the RMA i installed my 5 year old maxtor 80gb 2mb cache from my old pc. When i got the RMA back from WD i installed it as the slave drive to the maxtor, a month later the WD drive dies again so now im just using the old maxtor drive.

My question is how much of a performance hit am i taking speed wise by using a 2mb cache drive instead of a 8mb cache drive.
Im thinking about getting a new hard drive possibly a sata one( obviously not a Western Digital brand )
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Athlon 64 3000+@2.0ghz(stock)
Evga 6800GT 350/1000(stock)
Asus K8N-E deluxe nforce 3 250gb mobo
pc3200 ddr400 1024MB(2x512) XMS Corsair memory
80GB IDE Maxtor HD 2mb cache(Master)
120BG IDE WD HD 8mb cache(Slave) Died!!
Lite-on DVD/CD RW
Sound blaster audigy 2 zs
Antec SLK3700-BQE Case with 350W PSU
Windows XP SP1, directx 9.0c, Nvidia 67.02 forceware drivers, nforce 5.10 mobo drivers

 

[charles555]

the larger cache improves the sustained throughput rate. The ATA level notes the max transfer...

So, my Western Digital 8mb cache only reads at 83mb/s while my IBM 2mb will read at 84mb/s, but the WD takes the IBM in sustained throughput by about 15mb/s.

they are on the same channel, so I think the IBM was reading at 90mb/s before I put in this 1.5 year old WD. I also more free space back then (so the edge of the platter wasn't taken.)

EDIT: I just got a reading of 89mb/s on the WD and 48mb/s sustained.