My brother bought a computer 3 summers ago and I want to upgrade his computer as a Christmas present. But the problem is that I personally didn't buy it he did, so i don't know any specs on it. I want to buy either a 256MB or 512 MB ram for it but do not know if it is pc-133 or pc-2100. The processor is an Intel Celeron 1.1 GHz. If anyone can help let me know. Thanks.