Just used the Crucial search on my motherboard.
CT25664AA800 2GB, 240-pin DIMM
shop for more GA-8N-SLI
DDR2 upgrades £ 14.99
Quantity should be numeric 4
£ 59.96
Subtotal £ 59.96
Ship-to Country: VAT Tax calculated at 15% for United Kingdom £ 8.99
Shipping:
Shipping £ 0.00
Estimated Total £ 68.95
Not bad for 8GB
PC2 6400 at that
Be really surprised if you can use all (4) slots on your Gigabyte mobo had several that brand in past & wouldnt even run with Ram in all 4 slots ! GL 
Totally agree, am only rubbing XP Pro so 4gb is enuff.
Tried 4 x 1gb when I booght the board and they ran too hot any way.
Ordered 2 x 2gb
Order date/time: 20 December 2008 15:54:21 (internet)
Invoiced 2nd
Delivered just now.
Will stick to using Crucial in future if no issues with the memory.
CT25664AA800 2GB, 240-pin DIMM
Upgrade for a Giga-Byte GA-8N-SLI (Rev 1.1) System
£14.99 (Ex. VAT)
2
£29.98 (Ex. VAT)Order subtotal:
£29.98 (Ex. VAT)
(Royal Mail Special Delivery (1-2 work days from dispatch))
Shipping charges £2.49
Total £37.34
